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MQ-MAS: Sensitivity Enhancement

User Manual Version 002

BRUKER BIOSPIN

237 (327)

CNST3

: 

(in ns) = 50. This is the maximum timing resolution that can be obtained 

on a shaped pulse, with AV or AVII hardware. However, if 

cortab

 is defined for 

that nucleus, 100 ns is the maximum timing resolution possible in a shaped pulse.

CNST31

:

 Magic angle spinning frequency, used for the calculation of the duration 

of the sweep and the echo delay.

The calculation of the sweep is done via an AU program called 

zg_dfs

. It calcu-

lates the sweep according to the parameters given above and stores it as a shape 
file, which is called dfs. After the calculation the AU program starts the acquisition. 
In order to ensure that the correct sweep is always used, it is advisable to enter 
the name of this AU program into the parameter 

aunm

, and start all acquisitions 

using the command 

xaua

. All that needs to be optimized now is the appropriate 

RF power level for the sweep, defined as parameter 

sp1

. As a first guess a value 

of 3 dB less RF power than for the excitation pulse should be used (i.e. 

SP1

 = 

PL11

 + 3 dB). You may use 

popt

 for the optimization, where 

SP1

 is decremented 

by 1 dB up to the same power level used for the excitation pulse (e.g. from 20 dB 
to 0 dB). Initially a sweep of one whole rotor period (i.e. 

L0

 = 1) can be used. The 

optimization of 

SP1

 can be repeated e.g. for half a rotor period, a quarter of a ro-

tor period and so on. With a shorter sweep you will find that higher RF power will 
be needed.

Figure 18.5. Example for popt to Set-up for Optimization of DFS.

Note that the option “The AU program specified in AUNM will be executed” is 
checked. This ensures that the sweep is recalculated for the variation of 

l0

 and 

stored in the shape file dfs. The initial value of 

l0

 is 1.

Figure 18.5.

 shows a 

popt

 window with successive optimization of 

SP1

 for sever-

al fractions of rotor periods 

l0

. Note that the check mark for “The AU program 

specified in AUNM will be executed” MUST be set, in order to force recalculation 
of the shape for each step of the optimization. In this case acquisition is run with 
the command 

xaua

,

 which ensures that the correct sweep is stored in the shape 

file dfs. In the above example optimization proceeds such that in the first run 

SP1

is varied from 20 to 0 in 21 steps. Then 

L0

 is set to 2 and 

SP1

 is again varied from 

20 to 0. Then 

l0

 is set to 4 and so on. 

Figure 18.6.

 shows results of the variation 

of the RF power level of sweeps with different durations. Experiments have been 
run at 20 kHz and optimization procedures for 1, 0.5, 0.25, and 0.125 rotor peri-
ods corresponding to 50, 25, 12.5, and 6.25 µs respectively have been run. One 
can see that as the duration of the sweep is reduced the required RF field ampli-
tude is higher. This is true when the spinning frequency is kept constant and the 
sweep is a smaller fraction of a rotor period and when the sweep is kept at e.g. 

Содержание Solid State NMR

Страница 1: ...Version Bruker BioSpin think forward NMR Spectroscopy Solid State NMR 002 AVANCE Solids User Manual...

Страница 2: ...erstreifen D 76287 Rheinstetten Germany Phone 49 721 5161 0 FAX 49 721 5171 01 E mail solids bruker de service bruker de Internet www bruker com The information in this manual may be altered without n...

Страница 3: ...a Wideline single frequency Probe 41 3 7 2 Shifting the Probe Tuning Range 42 3 7 3 Adding a Frequency Channel to a Probe WB probes only 48 3 8 Mounting the Probe in the Magnet Shim Stack 50 3 9 EDAS...

Страница 4: ...veats for Multi nuclear CP MAS Spectroscopy 102 6 5 Setup for Standard Heteronuclear Samples 15N 29SI 31P 102 7 Basic CP MAS Experiments 105 7 1 Pulse Calibration with CP 105 7 2 Total Sideband Suppre...

Страница 5: ...nt 171 13 4 Data Acquisition 173 13 5 Spectral Processing 174 14 Symmetry Based Recoupling 179 14 1 Pulse Sequence Diagram Example C7 181 14 2 Setup 181 14 2 1 Spectrometer Setup for 13C 183 14 2 2 Se...

Страница 6: ...ast Amplitude Modulation FAM 242 18 4 Soft Pulse Added Mixing SPAM 242 19 STMAS 245 19 1 Experimental Particularities and Prerequisites 245 19 2 Pulse Sequences 247 19 3 Experiment Setup 249 19 3 1 Se...

Страница 7: ...282 23 Modified W PMLG 285 23 1 Pulse Sequence Diagram for Modified W PMLG 285 23 2 Pulse Shapes for W PMLG 286 23 3 Setup 287 23 4 Parameter Settings for PMLG and DUMBO 287 23 5 Fine Tuning for Best...

Страница 8: ...8 BRUKER BIOSPIN User Manual Version 002 Contents...

Страница 9: ...slightly different names differing usually in the pulse program name extension Contact your nearest applications scientist if you do not find the experiment pulse program that you are looking for Use...

Страница 10: ...rsion is available whereas possible inconsistencies will be removed There is no incon sistency with TopSpin vs 2 1 Disclaimer 1 1 Any hardware units mentioned in this manual should only be used for th...

Страница 11: ...direct observe 19F CP 1H 19F 1H 13C 19F 13C low sensitivity direct observe 3 He 203 209 Tl 31P NH4 H2PO4 1H 31PCP 0 powdered sample piezoelectric 4s 7 Li LiCl MAS 117 119 Sn Sn cyclohexyl 4 Sm2Sn2O7 S...

Страница 12: ...00 200 HH setup 8ms contact d1 10s 3ms d1 4s 113Cd Cd NO3 2 4H2O CPMAS 350 15ms contact d1 8s 195 Pt K2Pt OH 6 CPMAS 12000 1ms contact d1 4s 199Hg Hg acetate 2 Hexakis dimethyl sulphoxide Hg II triflu...

Страница 13: ...3 MAS CPMAS 70 1scan 500s finely powdered 50 ms contact 10 s repetition 1 scan 89 Y Y NO3 3 6H2O CPMAS 50 10ms contact d1 10s Literature J M Hook P A W Dean and L C M van Gorkom Magnetic Resonance in...

Страница 14: ...14 327 BRUKER BIOSPIN User Manual Version 002 Test Samples...

Страница 15: ...le images for WB and SB probes where non trivial differences exist Connections to the Preamplifier on page 15 RF Connections Between Preamplifier and Probe on page 20 RF Filters in the RF Pathway on p...

Страница 16: ...anged For broadband high power preamplifiers it is important to insert the ap propriate matching box into the side of the preamp Figure 3 1 All Connections to the Back of the Preamplifier RF cables fr...

Страница 17: ...Preamplifier The lock preamplifier is located at the bottom of the stack the transmitter cable carries the lock pulses For sol ids this preamp is normally not re quired When the transmitter cables are...

Страница 18: ...18 327 BRUKER BIOSPIN User Manual Version 002 General Hardware Setup Figure 3 3 The edasp setpreamp Display Note for Figure 3 3 Transmitter to preamplifier wiring must reflect hardware con nections...

Страница 19: ...er Stack 1 1 RF signal out to receiver 2 Lock signal out to lock receiver 3 Tune RF in from SGU 2 aux out 4 PICS probe ID cable to probe 5 ATMA and AUX connectors 6 RS 485 control connection and DCin...

Страница 20: ...ase the matching box or to the transmitter This applies to filters preamplifiers and matching boxes Es pecially if liquids preamps are used for solids work as well power limitations as frequency limit...

Страница 21: ...LNA preamplifiers are strictly frequency selective a 19 F pulse through a 1 H HPLNA will destroy it RF Filters in the RF Pathway 3 3 RF filters are frequently required if more than one frequency is tr...

Страница 22: ...this filter does not pass 2 Make sure the pulse power you apply does not exceed the power rating of this filter Most modern Bruker filters will survive 1 kW pulses of 5msec but older fil ters or non...

Страница 23: ...mps of the same kind next to each other in order to avoid incorrect wiring of probe and filters For the X channel only the proton frequency needs to be filtered out if X or Y is not decoupled while Y...

Страница 24: ...ation with 19 F and 1 H decoupling WB probes 400 MHz only For SB probes and 400 MHz different hardware is used A set of 1 H transmitter bandpass preamp and 19 F transmitter bandpass preamp is re quire...

Страница 25: ...were delivered without Probe Identification System PICS Probes delivered since 2007 are equipped with PICS Please refer to Figure 3 4 to identify the PICS port at the preamplifier cover module The pr...

Страница 26: ...ed to provide the spin ner bearing and drive gas Please refer to the installation or site planning manuals to learn about the gas requirements The most important parameters are Mains pressure should b...

Страница 27: ...lly expensive repair Using boil off nitrogen should be carefully considered since it is by far the most reliable stable and trouble free source of compressed gas to be used at any temperature Connecti...

Страница 28: ...gure 3 15 WB DVT Probe MAS Tubing Connections Figure 3 16 VTN Probe MAS Tubing Connections Note WVT Probes are VTN Type Probes 1 VT gas only input into dewar 2 Two thermocouple connectors 3 Drive gas...

Страница 29: ...easurements 1 Sample insert eject 2 Eject gas in 3 Insert gas in 4 Flush gas for transfer tube 5 T piece to insert tube allows the flush gas to be fed in at low temperature to avoid ice formation on s...

Страница 30: ...r eject Magic Angle 8 to tilt stator into the magic angle Bearing sense to supervise bearing pressure shut down in case of a pressure loss For LT experiments the ball joint at the heater dewar must be...

Страница 31: ...DVT In any case the VT control gas will flow through a dewar which contains a heater There will be at least one thermocouple which senses the temperature as close as possible to the sample Several req...

Страница 32: ...t air is sucked into the eject tube which would lead to formation of ice on low temperature runs This requires to maintain some overpressure above the spinner usually by applying some flow to the inse...

Страница 33: ...he upper thermocouple connector read located at stator out lower thermocoupler connector regul located at stator inlet are connected The VT unit must have the auxiliary sensor module to read more than...

Страница 34: ...7 BRUKER BIOSPIN User Manual Version 002 General Hardware Setup Figure 3 23 SB Probe MAS VTN Figure 3 24 SB Probe MAS DVT Connections 1 Probe heater connector 2 VT gas in 3 TC connector s 4 Frame flus...

Страница 35: ...RUKER BIOSPIN 35 327 Figure 3 25 WB Wideline or PE Probes Figure 3 26 WB Wideline or PE Probe Connections 1 Bell shaped glass dewar around sample chamber 2 Insulating and sealing Al2O3 felt ring 3 Cov...

Страница 36: ...Hardware Setup Figure 3 27 Low Temperature Heat Exchanger for VTN Probes old style In the figure above is a low temperature heat exchanger for VTN probes old style 1 turn exchanger loop for SB probes...

Страница 37: ...for DVT Probes The low temperature heat exchanger for DVT probes in the figure above uses the exchanger coil with 6 turns the larger one may be used for high resolution probes To use the spring loade...

Страница 38: ...General Hardware Setup Figure 3 29 Low Temperature Liquid N2 Dewar with DVT Probe Heat Exchanger 1 Nitrogen exhaust refill 2 Transfer line to probe DVT 3 VT Gas flow from B VT 3000 4 N2 level control...

Страница 39: ...002 BRUKER BIOSPIN 39 327 Figure 3 30 Bottom view of Low Temperature DVT Probe Heat Exchanger 1 Gas in 2 Frame flush 3 Shims 4 Spin rate 5 Heater 6 Magnet bore 7 Transfer line 8 Read and regulation t...

Страница 40: ...with B CU X or B CU 05 In the figure above is the low temperature setup with a B CU X or B CU 05 for DVT probes only shown from the probe magnet side 1 B CU X heat exchanger and transfer line 2 Bypas...

Страница 41: ...e desired task as much as possible A wideline probe has to cope with a large range of frequencies and line widths and must provide the shortest possible puls es and highest possible sensitivity at the...

Страница 42: ...r shortened Most probes are tuned over a certain range by variation of a capacitance The frequency range is then determined by the minimum and maxi mum capacitance that can be set In order to make the...

Страница 43: ...ollowing ways Figure 3 34 1 Switch the proton transmission line between 4 low range and 2 mode high range The proton transmission line is also part of the X circuit and is higher lower in capacitance...

Страница 44: ...up on ly In 300 MHz and lower probes only a 4 line can be used because a 2 would be too long but here 4 can be tuned over the full range All these modifications may be available for WB probes In SB pr...

Страница 45: ...transmission line Since such a line is as well an inductance as a capacitance it is a resonating circuit If the length of the transmission line equals 4 or 2 of the RF wave it is a 4 or 2 line Since...

Страница 46: ...o a higher higher frequency shorter length or lower lower frequency longer length position Figure 3 36 A 4 only probe left and a 4 2 probe right On the left side of the figure above is a 4 only probe...

Страница 47: ...or due to losses in Q if the coil becomes too large increase in resistance Furthermore capaci tances are tunable inductances usually are not so a wide tuning range can only be achieved via exchangeabl...

Страница 48: ...a Probe WB probes only 3 7 3 Probes are produced as single channel double channel triple or quadruple probes 1 2 or 3 RF connectors on the probe It is not possible to modify a probe produced as a doub...

Страница 49: ...specified frequency in this case 13 C while the Y fre quency has a broader tuning range in this case 15 N 2 H With different filter inserts that same probe can be modified to different frequency combi...

Страница 50: ...m below and above to mount the probe and the sample insert devices and also to the possibility to place VT equipment liquid N2 dewar B CU 05 or B CU X in a convenient location that allows access witho...

Страница 51: ...setpreamp with NMR Super user permissions does that Channel F1 is the detection channel by default which is no limitation Detection must usually be routed via the same SGU as the F1 pulses are since...

Страница 52: ...n error message or a warning will pop up Error messages will not allow selection of this routing On AVIII instruments with SGU 2 one SGU can produce two pulse trains within the same NCO frequency sett...

Страница 53: ...C routed via 500W trans mitter since 13 C requires less power than 15 N Figure 3 42 Long Display Pulse and Receiver Routing The figure above is a long display with pulse and receiver routing Green do...

Страница 54: ...SGU2 is used for pulsing and the SGU1 is used to receive Figure 3 44 The edasp Display for a System with two Receiver Channels In the figure above the edasp display for a system with two receiver cha...

Страница 55: ...also be explained This is part of probe setup and performance assessment during installation However regularly scheduled performance measurements should be part of the hardware probes and spectromete...

Страница 56: ...mit must be applied and that currents of far more than 20 A occur It is therefore essential that Power levels for pulses must be carefully considered before they are applied Always start at very moder...

Страница 57: ...n hardware connections the routing is under software control where possible Where cable connections need to be done manually the software does not allow a change These connections are made during inst...

Страница 58: ...always the observe nucleus To set up for 79 Br observation click on Default and the correct routing will be shown The green dot between SGU1 and amplifier 1 indicates that for this nucleus in this con...

Страница 59: ...s to the preamplifier with appropri ate filters placed on a table for better illustration Setting Acquisition Parameters 4 2 2 Create a new data set for the experiment by typing edc in the command lin...

Страница 60: ...02 Basic Setup Procedures Figure 4 3 Pop up Window for a New Experiment Spin the KBr sample moderately 5 2 5 mm 10 kHz In order to set up the ex periment type ased in the command line to open the tabl...

Страница 61: ...r level at which p1 is executed is pl1 Having high power transmitters it is important to be aware of the pulse power that is applied With TopSpin 2 0 and later ased shows pl1 and pl1w if the transmitt...

Страница 62: ...gure above the experiment button for opening the graphical display is marked with a red circle Then match and tune the probe for this sample using the command wobb This will start a frequency sweep ov...

Страница 63: ...off the zero line If tuned to a frequency within SFO1 WBSW 2 but SFO1 the probe response will be off center N B Fake resonances may appear which do not shift with probe tuning It is al ways a good id...

Страница 64: ...327 BRUKER BIOSPIN User Manual Version 002 Basic Setup Procedures Figure 4 7 Display Example of an Off Matched and Off Tuned Probe Figure 4 8 Display Example Where Probe is Tuned to a Different Freque...

Страница 65: ...he center peak see Figure 4 13 and start xau angle This will allow you to view the fourier transformed spectrum or the FID after ns scans The magic angle is adjusted best when the spikes on the FID or...

Страница 66: ...he routing for a double resonance experiment e g a 13C experiment with 1H decoupling For high power transmitters the parameter pow mod must be set to high To check which power mode is selected one may...

Страница 67: ...dot does not appear in the 1 H channel in edasp Connect the probe proton chan nel to the proton preamp A proton band pass filter must be inserted between pre amp and probe Tune the proton channel of...

Страница 68: ...BIOSPIN User Manual Version 002 Basic Setup Procedures Figure 4 12 Proton Spectrum of Adamantane at Moderate Spin Speed Set the carrier frequency O1 on top of the biggest peak using the encircled butt...

Страница 69: ...quency set the position of the cursor line and left click on the o1 button Acquire another spectrum ft and phase Then expand the spectrum around the adamantane proton signal including the spinning sid...

Страница 70: ...up Procedures Figure 4 14 Expanding the Region of Interest Click right mouse button in the Spectrum window When the Save Display Re gion to menu pops up select Parameters F1 2 and OK or type dpl in th...

Страница 71: ...art optimize to start the optimization procedure The parameter value obtained by the program is written into the parameter set of the actual experiment at the end of the optimization In order to stop...

Страница 72: ...ained at 6 sec in this case Once you have obtained a 90 degree pulse for a given power setting you can cal culate power levels for different rf fields using the AU program calcpowlev Type xau calcpowl...

Страница 73: ...prg2 cw Set pl12 to the power level that yields a 4 5 sec proton pulse Set pl1 such that in ased the power displayed is 200W for 13 C 7mm probe 150W 4mm probe or 80W 2 5 mm probe If the green dot is n...

Страница 74: ...D with 50 msec aq with setsh display showing no shim values N b spinning removes part of the B0 in homogeneities Probes which do not use susceptibility compensated coil wire can show much shorter T2 a...

Страница 75: ...l 73 1795 1818 2001 for reference Set the 13 C low field signal of adamantane to 38 48 ppm This will set the param eter SR which is used to calculate the chemical shift axis and the peak positions in...

Страница 76: ...me If this condition Hartmann Hahn condition is met the transfer of proton magnetization to carbon is optimum Since the pro ton signal of adamantane is resolved into spinning sidebands even at slow sp...

Страница 77: ...roton contact RF field from 50 to 100 sp0 set to pl12 3 dB to account for the lower average RF over the ramp p15 2 5 msec after the value specify m to make it milliseconds else it is tak en as microse...

Страница 78: ...the intensities are very sensitive to the RF level which is varied in 0 2 dB steps Using a ramp makes the experiment much more stable and more quantitative Problems may arise if the proton T1 is short...

Страница 79: ...and since packing of the spinner determines crucially the achiev able S N value it is useful to prepare a reference spinner with pure glycine fine ly powdered and densely packed glycine is prepared b...

Страница 80: ...erate Power Using cw Decoupling Since the proton spectrum of glycine extends around 5 ppm the optimum decou pler offset will be obtained at higher frequency than the adamantane proton peak around 1 2...

Страница 81: ...varies with the magnetic field At fields below 9 4 Tesla 400 MHz this line is substantially broadened by second order quadrupolar inter action to 14N At fields above 9 4 Tesla 500 MHz and higher the r...

Страница 82: ...eter Value Comments PULPROG cp cp av for AV1 and 2 NUC1 13C Nucleus on f1 channel O1P 100 ppm 13 C offset NUC2 1H Nucleus on f2 channel D1 4 s Recycle delay NS 4 Number of scans SWP 300 ppm Spectral w...

Страница 83: ...outine calculates 80 1 S N using 250 to 50 ppm spectrum range 50 to 40 signal range and 10 ppm noise range On this triple probe more than 100 1 is expected What else needs to be opti mized Two more pa...

Страница 84: ...2 sec observing the peak at 43 ppm which is more sensitive to decoupling mis sets Here this led to another 10 improvement in S N Good Laboratory Practice requires that evaluation measurements be take...

Страница 85: ...the probe into the lab notebook and start retuning to the new nucle us frequency from this frequency on following the probe response over the whole frequency range using a large wbsw of 50 MHz Altern...

Страница 86: ...orse have the probe checked Usually this means that dirt has accumulated inside the turbine or on the RF coil Cleaning should be done by a trained person only Regular probe performance checks comprise...

Страница 87: ...may also drift to higher frequency but this will change so it makes no sense to account for this initial drift A nonlinear drift pattern indicates temperature changes abrupt changes reveal magnetic di...

Страница 88: ...iupac reports provisional abstract01 harris_310801 html Cross polarization 1 D Michel and F Engelke Cross Polarization Relaxation Times and Spin Diffusion in Rotating Solids NMR Basic Principles and P...

Страница 89: ...the decoupled spins usually protons with RF of constant amplitude and phase The decoupling program is called cw or cw13 and it uses pl12 or pl13 respectively The decoupling programs select the power...

Страница 90: ...elds 300 MHz The figure below shows an arrayed optimization using popt for the TPPM phase tilt and pcpd2 available in TS2 0 and higher Figure 5 1 Optimization of TPPM Decoupling on Glycine at Natural...

Страница 91: ...P K Madhu J Magn Res 193 77 2008 XiX Decoupling 5 1 5 XiX decoupling requires high spinning speeds but decouples at a moderate RF level 180 proton pulses are used synchronized to the rotor speed such...

Страница 92: ...tiple Pulse Decoupling Observing dipolar couplings and j couplings to homo nuclear coupled nuclei Homonuclear couplings between abundant spins usually protons superimpose their heteronuclear dipolar c...

Страница 93: ...ilable to achieve such a frequency switch experimentally One method is simultaneous switching of frequencies and phases The other method uses phase modulation Frequency time and phase relate to each o...

Страница 94: ...94 327 BRUKER BIOSPIN User Manual Version 002 Decoupling Techniques Figure 5 3 FSLG Decoupling Pulse Sequence Diagram Figure 5 4 Adamantane FSLG decoupled showing the downscaled C H J couplings...

Страница 95: ...e include file lg calc incl which calculates the required frequency shifts to either side shown in ased as cnst22 and cnst23 Cnst24 provides an additional overall offset to compensate for phase glitch...

Страница 96: ...nance it can easily be calculated that a phase change over 209 during a 293 flip angle pulse is required to achieve this Figure 5 5 Shape with Phase Gradients In the figure above Shape with phase grad...

Страница 97: ...in Solids Chem Phys Lett 155 341 346 1989 2 A Bielecki A C Kolbert H J M deGroot R G Griffin and M H Levitt Frequency Switched Lee Gold burg Sequences in Solids Advances in Magnetic Resonance 14 111 1...

Страница 98: ...ally dominant J0 term describing coherent residual line broadening effects in the transverse relaxation rate R2 A Abragam chapter 8 With the normal CP experiment the observed line broadening coherence...

Страница 99: ...cult 1 Low concentration of 13 C in the sample 2 No or too few protons in the sample 3 Long proton T1 4 Long TI S 5 Short proton T1 If a nucleus different from 13 C should be observed there are additi...

Страница 100: ...for proton ob servation set swh to 100000 500000 rg to 4 and pulprog cpopt if not found in the library copy the pulse program in the appendix p3 and pl12 for p3 p90 Set spnam0 ramp 100 sp0 power leve...

Страница 101: ...the power in watts So if ased shows pl1W 150W for a well optimized 13C CP setup 15 N will require 6 25 150 W 938 W This is far above specs so the same proton contact power level cannot be used it need...

Страница 102: ...age for the X contact pulse of the known 13 C HH condition calculate the pp voltage for the unknown HH condition from the NMR frequencies of the two nuclei and set this voltage for the unknown HH cond...

Страница 103: ...ze HH condition acquire reference spectrum with aq 25 35 ms 2 29 Si on DSS load glycine 13 C reference spectrum set observe nucleus to 29 Si in edasp add 2 dB to sp0 acquire 4 scans with aq 35 ms opti...

Страница 104: ...104 327 BRUKER BIOSPIN User Manual Version 002 Practical CP MAS Spectroscopy on Spin 1 2 Nuclei...

Страница 105: ...square 100 or using the pulse program cplg Pulse Calibration with CP 7 1 Pulse calibration for 13 C pulses after cross polarization using a flip back pulse Figure 7 1 Pulse Program for CP with Flip b...

Страница 106: ...ses are set with pl11 This experiment can be optimized for minimum spinning sideband intensity either by variation of the 180 pulse width or the associated power level pl11 Two variations of the TOSS...

Страница 107: ...ic Resonance Spectroscopy 35 1999 203 266 The SELTICS sequence is an alternative Set up the experiment using glycine or tyrosine HCl at a moderate spinning speed Get a good CPMAS spectrum first then r...

Страница 108: ...th a long phase cycle requiring a minimum of 243 transients for complete artifact suppres sion using the pulse program cptoss243 where the extension av is added in case of the AV2 console Figure 7 4 s...

Страница 109: ...ine HCl at 6 5 kHz Figure 7 4 is a CPTOSS243 experiment on tyrosine HCl at 6 5 kHz sample rota tion using a 4 mm CPMAS triple resonance probe at 500 MHz with 243 accumu lated transients No spinning si...

Страница 110: ...ak to peak compared to the highest intensity The residual sidebands have up to 5 intensity compared to the highest resonance SELTICS 7 3 Like the TOSS experiment SELTICS Sideband ELimination by Tempor...

Страница 111: ...lse Program for SELTICS In Figure 7 6 one can see that the SELTICS experiment takes only rotor period compared to the 2 rotor periods required in the TOSS experiment Use glycine or tyrosine HCl at rea...

Страница 112: ...ared to the original spectrum without sideband suppression 256 tran sients were recorded Figure 7 8 Cholesterylacetate Spectrum Using Sideband Suppression Figure 7 8 is a cholesterylacetate spectrum u...

Страница 113: ...lar in teraction For the dephasing delay d3 one uses between 30 and 80 s Figure 7 9 Block Diagram of the Non quaternary Suppression Experiment The non quatemary suppression experiment is also called t...

Страница 114: ...ic CP MAS Experiments Figure 7 10 Glycine 13 C CPMAS NQS Experiment with a Dephasing Delay Figure 7 10 is a glycine 13 C CPMAS NQS experiment with a dephasing delayd3 40 s so that the total dephasing...

Страница 115: ...NQS Experiment with TOSS Figure 7 11 is a tyrosine 13 C CPMAS NQS experiment with TOSS using a de phasing delay d3 60 s Spinning sidebands are suppressed for a clean spec trum In this experiment the...

Страница 116: ...better editing p17 for the repolarization step in the CPPIRCP ex periment is about 10 20 s For this experiment to succeed reliably one should use moderate spinning speeds around up to 10 kHz At slow...

Страница 117: ...PPIRCP experiment with p16 40 s and p17 10 s for better nulling of CH resonances but in this case the aromatic CH resonances gained some intensity back The purple first spectrum is a CPPISPI experimen...

Страница 118: ...118 327 BRUKER BIOSPIN User Manual Version 002 Basic CP MAS Experiments...

Страница 119: ...the protons In this case the proton magnetization detected by the X nucleus comes from close protons only since the proton spin lock at an LG offset interrupts the communication between the proton spi...

Страница 120: ...xperiment The FSLG Hetcor experiment consists of 3 basic elements the homonuclear de coupling sequence during which the 1H chemical shifts evolve the cross polariza tion sequence during which the info...

Страница 121: ...pl12 set cnst20 to RF field in Hz as calculated from p3 5 Generate a new data set with edc new Set pulprog lghetfq and change to a 2D parameter set using the 123 button in eda Set FnMode to STATES TPP...

Страница 122: ...122 327 BRUKER BIOSPIN User Manual Version 002 FSLG HETCOR Figure 8 3 The ased Display...

Страница 123: ...1 for contact pulse pl12 Power level channel 2 TPPM SPINAL decoupling pl13 Power level channel 2 FSLG decoupling sp0 Power level channel 2 for contact pulse spnam0 ramp 100 or simil Shape for contact...

Страница 124: ...ion 002 FSLG HETCOR Table 8 2 Processing Parameters for FSLG HETCOR on tyrosine HCl Parameter Value Comment F2 direct dim 13C si 2 4 k wdw QSINE SSB 2 3 or 5 ph_mod pk F1 indirect 1H si 256 1048 mc2 S...

Страница 125: ...own in Table 8 1 Table 8 2 Full transform with slight resolution enhance ment qsine SSB 3 Proton shifts calibrated as 2 5 and 12 most high field low field peak Center ridge at 0 ppm along F1 is spin l...

Страница 126: ...or Spectrum Tyrosine HCl The figure above shows a FSLG Hetcor Spectrum Tyrosine HCl with parameters as shown in Table 8 1 Table 8 2 Full transform with slight resolution enhance ment qsine SSB 3 Proto...

Страница 127: ...h can be timed in exact analogy to the CRAMPS type se quences wpmlg 2 and dumbo 2 These sequences also suppress the center ridge efficiently so that the carrier frequency need not be shifted out of th...

Страница 128: ...At long contact times and transfer from many different protons the line width in the proton spectrum may also be insensitive In fig 1 two columns through the most up field aliphatic peak in tyrosine...

Страница 129: ...ase modulated Lee Goldburg decoupling sequences Chem Phys Lett 2002 354 193 4 Leskes Michal Madhu P K Vega Shimon A broad banded z rotation windowed phase modulated Lee Goldburg pulse sequence for 1H...

Страница 130: ...ing Leskes et al Chem Phys Lett This allows reduced measure ment times Pmlghet wpmlghet dumbohet and edumbohet should give rather similar spectra Table 9 1 Acquisition Parameters for pmlg HETCOR on ty...

Страница 131: ...upling sequence F1 1H indirect l0 0 Start value 0 incremented during expt l3 2 4 Multiples of FSLG periods increment per row in_f1 in0 as calculated Set according to value calculated by ased F2 13 C a...

Страница 132: ...t20 usually 100 kHz As prepared with wpmlgd proton detect exp cnst24 1000 3000 Place carrier within proton spectrum for evolution pl1 Power level channel 1 for contact pulse pl12 Power level channel 2...

Страница 133: ...iate for an RF field of 100 kHz Spnam2 is set to edumbo22_1 0 Table 9 4 Acquisition Parameters for e DUMBO HETCOR on tyrosine HCl Parameter Value Comments pulprog edumbohet windowless dumbo shape nuc1...

Страница 134: ...g just the knowledge of the RF power level for decoupling at a certain RF field Setting cnst20 to this RF field 5 or 10 is all that needs to be set if the 13 C observe parameters are well adjusted F2...

Страница 135: ...is required on F1 with increasing offset So it is recommended not to set the proton power higher than to 50 kHz RF field For the setup the pulse program lgcp is used It contains an include file lgcal...

Страница 136: ...lds 74000 or 48000 Hz If a 30 ramp is used and sp0 is set to 74000 with a safety margin of 1000 the HH condition will cover 75000 down to 45000 Hz RF field This includes both HH sidebands n 1 4 Optimi...

Страница 137: ...e in order to achieve efficient recovery of single spin magnetization and to generate an effective dipolar recoupling Hamiltonian during the mixing period The critical experimental point is to avoid 1...

Страница 138: ...r f field strengths used in the recoupling channel pl11 and the r f field on the 1H de coupling channel must be sufficiently different ca a factor of 3 to avoid rapid de polarization of the carbon si...

Страница 139: ...w data file and switch to the 2D mode using the 123 button Set the appropri ate FnMode parameter in eda Pulse program parameters are indicated below Figure 10 1 shows the pulse sequence Figure 10 2 Th...

Страница 140: ...nnel p1 90 excitation pulse on f1 channel p2 180 excitation pulse on f1 channel p3 90 excitation pulse on f2 channel p15 Contact pulse on f1 and f2 channel d0 3 t1 evolution period d1 Recycle delay cp...

Страница 141: ...ands FnMode STATES or STATES TPPI Table 10 2 Processing Parameters Parameter Value Comment F1 acquisition 13 C Left column si 4k Number of points and zero fill ph_mod pk Phase correction if needed bc_...

Страница 142: ...142 327 BRUKER BIOSPIN User Manual Version 002 RFDR Figure 10 4 2D RFDR Spectrum of 13C fully Labelled Histidine RFDR mixing time 1 85 ms...

Страница 143: ...very slow and requires very long mixing times since the dipolar cou pling between all X nuclei is small However turning the proton decoupling field off during the mix period allows another process to...

Страница 144: ...in Exchange by Two Dimensional Fourier Transform 13 C Cross Polarization Magic Angle Spinning J Magn Reson 47 462 475 1982 2 A F de Jong A P M Kentgens and W S Veeman Two Dimensional Exchange NMR in R...

Страница 145: ...ndard sample 3 If the real sample does tune and match very differently than the setup sample verify the HH conditions briefly and eventually the X 90 hard pulse 4 Set the spin rate as high as possible...

Страница 146: ...o the spin rate or such that sidebands folding in along F1 do not interfere 11 Make sure the correct nucleus is selected in the F1 dimension make sure to choose an appropriate quadrature detection mod...

Страница 147: ...r Window eda 14 Set pl14 if DARR RAD is desired else make sure pl14 120 dB For DARR RAD calculate the required power level using calcpowlev or use the setup pro cedure shown in 11 7 15 Start the exper...

Страница 148: ...PL14 for n spin rate DARR or 120 Recoupling SP0 For 1 H contact using shape SPNAM0 ramp 100 or ramp70100 100 For 1 H 13 C contact CPDPRG2 SPINAL64 At PL12 P1 13 C excitation flip pulse P3 1H excitatio...

Страница 149: ...o cw 3 Use the au program calcpowlev to calculate the power level required for a pro ton decoupling RF field of n masr using p3 and pl12 as reference values Refer to chapter Basic Setup Procedures on...

Страница 150: ...n 2 and n 1 RR conditions 26 and 13 kHz RF field 4 Vary the decoupler power level pl12 used with cw decoupling as indicated in Figure 11 3 from a power level value pl12 1 dB below the calculated n 1...

Страница 151: ...Driven Spin Diffusion PDSD User Manual Version 002 BRUKER BIOSPIN 151 327 Example Spectra 11 5 Figure 11 4 13 C CPSPINDIFF of fully labeled tyrosine HCl spinning at 22 kHz 4 6 msec mix Upper PDSD lowe...

Страница 152: ...ove is a comparison of DARR PDSD with 4 6 and 20 msec mixing time sample tyrosine HCl spinning at 22 kHz Traces through peak at 115 ppm most high field aromatic carbon Traces from below DARR at 4 6 ms...

Страница 153: ...Proton Driven Spin Diffusion PDSD User Manual Version 002 BRUKER BIOSPIN 153 327 Figure 11 6 13 C DARR of Fully Labelled Ubiquitine Spinning at 13 kHz...

Страница 154: ...154 327 BRUKER BIOSPIN User Manual Version 002 Proton Driven Spin Diffusion PDSD...

Страница 155: ...t with I refocusing pulse are subtracted and evaluated Refer ence experiment and dephased experiment can be acquired consecutively or in an interleaved mode so that experimental drifts will not cause...

Страница 156: ...rupolar nuclei These are for example the Rotational Echo Adia batic Passage DOuble Resonance REAPDOR or TRAnsfer of Population in DOuble Resonance TRAPDOR sequences Usually the setup is chosen such th...

Страница 157: ...lead to a well defined direct interaction between 15N and 13Ca so that a single frequency dipolar modulation is obtained A triple resonance probe with the X channel tuned to 13C and the Y channel tune...

Страница 158: ...t 5 One can reoptimise the refocusing pulse on the coupled nucleus using a 1D ver sion of redor setting the number of experiments 1 td to 1 Here the number of refocusing pulses l0 is chosen to a value...

Страница 159: ...a frame by interleaving scans of the S0 and S experiments for the same evolution period see Figure 12 2 cpredorxy8 increments in units of 16 rotor periods for small couplings Here the XY 8 scheme is u...

Страница 160: ...channel I S ex periment every even row 2 4 6 contains the corresponding echo experi ment S0 experiment with the same evolution period t after the RAW Data is processed with the XF2 command see Figure...

Страница 161: ...the first spectrum by using the extract slice button and select the desired peak by manual peak picking To save the data use the button shown in Figure 12 4 Figure 12 4 Saving Data to Continue to the...

Страница 162: ...every even line the corresponding intensity of the ECHO experiment S0 Figure 12 5 Setting the Correct Analysis Parameter After importing this file into Excel or any other program using either Origin...

Страница 163: ...ion for the measured spin system for details check reference 6 The more common way for the interpretation of the experiment is the second mo ment approach which is also suitable for multiple spin syst...

Страница 164: ...xperimental data points together with two different SIMPSON sim ulations for details of the geometry and distance information of the labelled 15 N 13 Ca spin pair of glycine see reference 9 The red si...

Страница 165: ...PSON will always suffer from the fact that a non optimal setup of the experiment will introduce the same error like a reduced dipolar coupling between the analyzed spins these two effects can not be e...

Страница 166: ...nsforms to an overall distance error of about 10 Afterwards the calculated M2 can be transformed into the dipolar coupling con stant by using Eq 12 4 The comparison of the second moment directly calcu...

Страница 167: ...ssary to proof the experimental setup on a known spin system like the glycine in order to check the robustness of the overall sequence setup After this validation and calibration process the sequence...

Страница 168: ...alumino silicates Chem Phys Lett 174 428 432 1990 6 K T Mueller Analytic solutions for the Time Evolution of Dipolar Dephasing NMR Signals Journal of magnetic resonance A 113 81 93 1995 7 T Echelmeyer...

Страница 169: ...requirements exist for 1H decoupling during the recoupling pulses because it uses 360 pulses instead of the 180 pulses in Tycko s experiment Exact 360 pulses automatically decouple the heteronuclear d...

Страница 170: ...rify pulse width 4 Calculate power level required for heteronuclear decoupling during the recou pling pulses pl23 i e 20 30 kHz or 25 x frot Low power decoupling during the recoupling pulses is permit...

Страница 171: ...r page is used to toggle to the different data acquisition modes 1D 2D and 3D if so de sired 9 Make sure the correct nucleus is selected in F1 dimension make sure an ap propriate quadrature detection...

Страница 172: ...172 327 BRUKER BIOSPIN User Manual Version 002 SUPER Figure 13 3 The Acquisition Parameter Window eda...

Страница 173: ...PL11 Power level for f1 recoupling P2 180 pulse on F1 during TOSS with PL1 PL2 Power level for f2 channel PL12 Power level decoupling f2 channel and excitation P3 Excitation pulse f2 channel P15 Conta...

Страница 174: ...r of points and zero fill WDW QSINE Squared sine bell SSB 2 90 shifted sine bell PH_mod pk Phase correction if needed BC_mod quad DC offset correction Alpha 1 For shearing the spectrum F2 indirect 13...

Страница 175: ...SUPER User Manual Version 002 BRUKER BIOSPIN 175 327 Figure 13 4 The SUPER Spectrum of Tyrosine HCl After Processing Using xfb...

Страница 176: ...UPER Figure 13 5 SUPER spectrum after tilting the spectrum setting 1 alpha 1 The figure above is a SUPER spectrum after tilting the spectrum setting 1 alpha 1 and using the command ptilt1 repeatedly u...

Страница 177: ...sion 002 BRUKER BIOSPIN 177 327 Figure 13 6 Various Cross Sections from the Upper 2D Experiment The figure above illustrates various cross sections from the upper 2D experiment from which CSA paramete...

Страница 178: ...178 327 BRUKER BIOSPIN User Manual Version 002 SUPER...

Страница 179: ...the cycle n is the number of rotor periods spanned by the N elements and the total phase rotation between the elements is 2 In the simplest imple mentation of a C sequence the 2 rotation element is s...

Страница 180: ...sensible setup Table 14 1 shows the selection parameters for three standard recoupling sequences References 1 E A Bennett R G Griffin and S Vega Recoupling of homo and heteronuclear dipolar interacti...

Страница 181: ...the proper choice of hardware for the observe nucleus 13 C Obviously observation of DQ co herence requires samples with reasonable dipolar couplings and reasonable probability of coupled species So ru...

Страница 182: ...bes and not too high fields 3 SC14 or sequences with similar RF field requirements are recommended for small spinners high fields 4 Maximum speed results from max possible RF field 5 Maximum 13 C RF f...

Страница 183: ...to 120 dB p1 to zero and run 1 experiment with 16 4 scans as a reference Setup for the Recoupling Experiment 14 2 2 1 Create a new experiment and load the appropriate pulse program spc5cp1d use the s...

Страница 184: ...aks must grow together as one approaches the RF 7 MASR condition but the resonances are differently influenced by non ideal off HH condi tions The glycine peak is usually hard to get off HH so it is f...

Страница 185: ...illustrates PC7 recoupling efficiency at a spinning speed of 13 kHz about 100 kHz RF field using a 2 5 mm probe LG decoupling at 125 kHz was used during DQ generation reconversion Quite a noticeable l...

Страница 186: ...but provide a larger sweep width and less fold over M Hong 1999 Fold over can often be tolerated xfshear rotate may be used to shift the spec trum suitably along F1 13 Set the acquisition time along F...

Страница 187: ...7 sc14 for full phase cycle SPNAM0 Ramp for 1st CP step e g ramp 80 100 SP0 Power level for proton contact pulse CPDPRG2 SPINAL64 SPINAL64 decoupling CPDPRG1 cwlg To avoid HH contacts during DQ genera...

Страница 188: ...sr 2 sr o1 will set the referencing along F1 correctly just type sr and in f1 en ter the value of sr for F2 and add 2 o1 Table 14 3 Processing parameters for DQ SQ correlation experiments using symmet...

Страница 189: ...along F1 spin rate only the correlation is folded 13C 13C Single Quantum Correlation with DQ Mixing 14 5 Symmetry based DQ recoupling sequences may also be used as mixing periods in SQ SQ correlation...

Страница 190: ...tion pulse f2 channel PCPD2 Decoupler pulse length f2 channel 1H TPPM P15 Contact pulse D1 Recycle delay CNST20 Spin nutation frequency at PL13 for cwlg decoupling L0 for 0 5 10msec mix in ased Use mu...

Страница 191: ...right 56 rotor periods mixing The 84 periods mixing time show relayed correlations positive blue which are absent at 56 periods mixing except for the SSB cross peaks Direct correlations are negative...

Страница 192: ...192 327 BRUKER BIOSPIN User Manual Version 002 Symmetry Based Recoupling...

Страница 193: ...ion of spin exchange dipolar flip flop term and the homo nuclear decoupling using FSLG PISEMA achieves a line width that is an order of magnitude better than its predecessor the separated local field...

Страница 194: ...NMR Correlation Spectroscopy J Magn Reson 140 131 140 1999 3 A Ramamoorthy and S J Opella Two dimensional chemical shift heteronuclear dipolar coupling spectra obtained with polarization inversion sp...

Страница 195: ...a LG offset load the pulse program cplg Cnst 17 sets the LG offset during the contact the offset frequencies are calcu lated as cnst 18 and cnst19 Start with cnst17 0 4 Two possibilities exist to set...

Страница 196: ...ditions briefly and verify that the found parameters are valid Correct power levels or pulse parameters if needed This is especially impor tant for saline lipid water mixtures 8 Depending on the decis...

Страница 197: ...ring t2 PL13 For 1H Evolution under FLSG condition P3 1H excitation pulse P15 15N 1H Contact pulse P6 1H LG 294 degree pulse D3 1 4 s For frequency phase setting D X only cnst20 1H spin nutation frequ...

Страница 198: ...mand edmac and the filename pisemaft for examples write the following com mands using the text editor xf2 zeroim xf1 5 Save and close the edmac editor 6 In the future you can do then the processing b...

Страница 199: ...n 002 BRUKER BIOSPIN 199 327 Figure 15 2 PISEMA Spectrum of 15N Labeled Acetylated Valine and FID in t1 over 3 008 ms 64 Data Points A PISEMA Spectrum of 15 N Labeled Acetylated Valine B FID in t1 ove...

Страница 200: ...002 PISEMA Figure 15 3 PISEMA Spectrum of 15N Labeled Kdpf Transmembrane Protein PISEMA spectrum of 15N labeled Kdpf transmembrane protein aligned in DMPC courtesy of NHMFL Dr T Cross membrane between...

Страница 201: ...ples of nuclear magnetism Oxford Clarendon Press 1961 but simpler descriptions can be found in the books of Slichter and Levitt C P Slichter Principles of magnetic resonance Springer 1996 3rd ed M H L...

Страница 202: ...laxation via a particular energy level transition fields fluctu ating with an inverse correlation time close to the frequency of the transition are required Longitudinal relaxation occurs via transiti...

Страница 203: ...ent is preferred Here the transitions are saturated by a rapid sequence of hard pulses such that no signal remains There is then a variable delay during which relax ation occurs and then a 90 read out...

Страница 204: ...as in Figure 16 1 Since this is a pseudo 2D experiment the only relevant parameter in F1 is the number of points which should be the number of entries in the vd list The most important setting is the...

Страница 205: ...frequency di mension does not affect the analysis so exponential multiplication with lb of the order of the observed line width can be applied to improve the signal to noise ra tio Table 16 2 Paramete...

Страница 206: ...llow you to move between the integral regions exclude points from the calculation display the data on a va riety of axes and start the fit for the displayed region or all regions Figure 16 1 shows the...

Страница 207: ...results of the fit including the de tails of the fit function and the calculated values of the parameters in the function The experimental and calculated data points are also displayed Note that the...

Страница 208: ...ter Basic Setup Procedures Set d1 to a rela tively long value for the preparation experiments Set the number of pulses in the saturation train l20 to zero and acquire a spec trum This will give an ide...

Страница 209: ...pin lock time The parameters of cross polarization can also be de termined from variable contact time CP experiments the function cpt1rho is pro vided in the relaxation analysis tool for this purpose...

Страница 210: ...e with shortest spin lock time contains most signal so this slice should be used for processing The fitting function should be set to expdec and vplist should be selected as the list file name in the...

Страница 211: ...Saturation parameters can be set as for carbon saturation previously l20 5 100 and d20 1 50 ms Acquire a spectrum with these parameters and verify that there is again no signal Make a new data set wit...

Страница 212: ...212 327 BRUKER BIOSPIN User Manual Version 002 Relaxation Measurements...

Страница 213: ...ple 1D spectrum The 2D MQMAS experiment exploits the fact that the 2nd order broadening of the symmetric MQ transitions e g 3 2 3 2 in a spin 3 2 is related to the 2nd order broadening of the CT by a...

Страница 214: ...4 are the incremented delay for t1 evolution and 20 s for z filter respectively Phase lists are as follows for phase sensitive detection in F1 the phase of the first pulse must be incremented by 30 in...

Страница 215: ...ty to facilitate the set up and c a 2nd order quadrupole interaction in the order of the one expected for your sample of interest In the first step a low power selective pulse must be calibrated in a...

Страница 216: ...are no longer visi ble which is used as an indication that it is not excited Table 17 1 Some Useful Samples for Half integer Spin Nuclei Nucleus Spin Spectrometer Frequency 1 d1 s 3 Sample Comments 1...

Страница 217: ...excited with a 20 s selective 90 pulse Note that in the latter no spinning side bands from the satellite transition are observed Spectra are taken on AV500WB at a Larmor frequency of 163 6 MHz with a...

Страница 218: ...ith sensitivity enhancement methods like DFS or FAM see MQ MAS Sensitivity Enhancement on page 231 describing sensitivity enhancement methods In Table 17 2 the starting parameters for the set up are d...

Страница 219: ...r more details about using the popt procedure to optimize a series of parame ters please refer to the manual Figure 17 6 shows the signal amplitudes as func tions of pulse lengths p2 and p1 Table 17 2...

Страница 220: ...ge from 0 to 6 s for p2 from 0 to 2 s Two Dimensional Data Acquisition 17 3 2 Once the pulses are calibrated everything is ready for the 2D data acquisition Create a new data set and change parmode to...

Страница 221: ...td 2 in_010 For rotor synchronized experiments in_010 1 spinning frequency so will typical ly be between 100 s 10 kHz spinning and 28 5 s 35 kHz spinning so only 10 to 40 experiments in amorphous samp...

Страница 222: ...ield erroneous shearing When started the AU program prompts for Apply ABS2 and F1 shift in ppm It is ad visable to calculate a baseline correction after F2 Fourier transform Note that the range define...

Страница 223: ...number m which is determined by the experiment e g 3 2 in case of a 3Q experiment of an order p 3 The program stores the F1 shift that was calculated and will prompt for it when data are processed nex...

Страница 224: ...ional shift of 5 ppm respectively We see that without the additional shift the uppermost peak is at the border of the spectral range and the projection shows that the edge of this peak reenters into t...

Страница 225: ...es plot A In the op posite case of identical quadrupole couplings separation increases as the field is increased plot B In cases where a difference in isotropic chemical shift iso ex ists and the site...

Страница 226: ...0 5 90 270 5 Again an 18 phase increment of the first pulse for States or States TPPI phase sensitive detection in F1 is needed Thus a full phase cycle can be performed with a multiple of 160 scans Th...

Страница 227: ...hift position in the MQ dimension the so called SOQE parameter can be calculated dqis being given by equation 2 Eq 17 4 with Eq 17 5 f I equals 4 16 67 39 2 and 72 for I 3 2 5 2 7 2 and 9 2 respective...

Страница 228: ...shift is scaled down and subtracted from the isotropic shift to give the MQ shift In the example shown in Figure 17 10 two sites are vis ible with distinct differences in their spectroscopic parameter...

Страница 229: ...the slope F2 F1 1 there are two more lines drawn The blue axis indicated as axis Qis is the quadrupole induced shift axis with the slope F2 F1 17 10 This axis is identical for all different spins I an...

Страница 230: ...um this gives quadrupole induced shifts qis of 75 ppm and 20 ppm for the two sites respectively At 18 8 T the qis of the lower peak in the 2D spectrum decreases to 30 ppm whereas it cannot be determin...

Страница 231: ...y between the conversion pulse and the 180 pulse or the delay prior to the start of the acquisition must be incremented proportional to t1 This results in a split t1 experiment where the top of the sh...

Страница 232: ...the echo with the sample rotation i e make an integer multiple of rotor periods For FT of the shifted echo FID there is a slight inconvenience as shown in Figure 18 2 because after a normal FT the sig...

Страница 233: ...av In both sequences the same sweep is used Both sequences start with an excitation pulse p1 that creates 3Q coherence which is allowed to evolve during the evolution period D0 The sweep during P2 is...

Страница 234: ...nd D4 are the incremented delay for t1 evolution and 20 s for z filter respectively Delay D10 can be incremented for spin I 3 2 nuclei proportional to D0 Power level and duration of the sweep P2 must...

Страница 235: ...to build up If we assume the FID has decayed after 3 ms spinning frequency is 25 kHz and the 90 pulse is 20 s then L1 should be between 70 and 80 so that D6 is between 2 77 and 3 17 ms P2 Is calculate...

Страница 236: ...see text Calculated in pulse program P3 20 s 90 selective pulse at pl21 used in mp3qdfsz av only P4 40 s 180 selective pulse at pl21 used in mp3qdfs av only PL1 120 dB Not used PL11 Power level for e...

Страница 237: ...for half a rotor period a quarter of a ro tor period and so on With a shorter sweep you will find that higher RF power will be needed Figure 18 5 Example for popt to Set up for Optimization of DFS Not...

Страница 238: ...ield amplitude for double frequency sweeps 2D Data Acquisition 18 2 2 After the parameters for the DFS are adjusted the 2D data acquisition can be pre pared In tables 2 and 3 the important parameters...

Страница 239: ...alf rotor synchronization to double the spectral window in F1 may help However in this situation one set of spinning sidebands appears and it must be avoided that the spinning side bands of one peak f...

Страница 240: ...can be precisely adjusted in the interactive phase correction routine The phase of the spectrum must be corrected such that there is no signal in the imaginary part as described above Table 18 3 Param...

Страница 241: ...ly set to one times zero filling WDW no Don t use window function PH_mod pk Apply phase correction BC_mod no No DC correction is required after full phase cycle ABSF1 1000 ppm Should be outside the ob...

Страница 242: ...a range of frequencies These frequencies must lie in the range of the satellite tran sitions therefore a single frequency irradiation is sufficient for spin I 3 2 Higher spins have more satellite tran...

Страница 243: ...rt of the 2D data acquisition all that needs to be set is the pulse program mp3qspam av and a small number of other parameters These are list ed in Table 18 6 Table 18 6 Further Parameters for 2D Data...

Страница 244: ...he phase information care must be taken that the pure absorption line shape of the 2D peaks is not obscured Therefore in case of doubt it is probably the best idea to set L5 TD F1 2 If less anti echos...

Страница 245: ...TMAS experiment exploits the fact that the 2nd order broadening of the ST transitions e g 3 2 1 2 in a spin 3 2 is related to the 2nd order broad ening of the CT by a simple ratio A 2D spectrum is rec...

Страница 246: ...by the width of the satellite transition giving a length of e g 1 s for a satellite transition of 1 MHz width If the rotor period varies from that specified in the parameters the calculated delay in...

Страница 247: ...the basic sequences which are 4 pulse sequences with z filter stmasdqfz av and stmasdqfe av Both sequences start with a non selective excitation pulse p1 that creates SQ coherency on the in nermost ST...

Страница 248: ...ly to the t1 period a split t1 experiment as described in chapters 16 and 17 for some MQMAS experiments will be performed Figure 19 3 Four pulse sequence and coherence transfer pathway Four pulse sequ...

Страница 249: ...to Table 19 2 to select a suitable sample For the general procedure described here the spin I of the nucleus is not important of course the obtained pulse widths will depend on the spin I and the Larm...

Страница 250: ...d echo can be used in DFS enhanced MQMAS experiments In Table 19 3 and Table 19 4 the starting parameters for the setup of the two se quences are given Typical values for the pulses are entered so one...

Страница 251: ...ust be set according to Table 19 5 Similar considerations for the maximum t1 period determined by the number of FID s to be acquired and the t1 increment can be made as for MQMAS Because the shift ran...

Страница 252: ...sting the magic angle with KBr the right spectrum can be obtained after several iterations of readjusting the angle and rerunning the 2Dspectrum Table 19 5 F1 Parameters for the 2D Data Acquisition Pa...

Страница 253: ...ct dimension Using this procedure the shift positions in the indirect dimension are identical in ppm to all MQMAS exper iments and the information obtained is the same Table 19 6 Processing Parameters...

Страница 254: ...Basic MQ MAS on page 213 for details about the informa tion obtained from such spectra Table 19 7 Values of R and R p for the Various Spin Quantum Numbers Ob tained in the STMAS Experiment Spin I R R...

Страница 255: ...lar coupling is much smaller than any dipolar coupling involving protons For C N it is 2 5 kHz This has some ex perimental consequences 1 There is no need to decouple 15N while observing 13C since the...

Страница 256: ...cine 15N and C1 C2 or only C2 13C labelled Make sure the sample is glycine you will get nowhere with glycine since the proton T1 is very short and CP just does not work with high efficiency Rotate at...

Страница 257: ...ove the proton decoupling RF interference is required for X and Y This means that one of the band pass filters on X or Y may be replaced by a proton reject X low pass filter If the channel isolation b...

Страница 258: ...lse program and moving the carrier close to the C peak determine a power level pl11 which corresponds to 35 kHz RF 7 14 sec 90 pulse However since the sample spins at 11 kHz the HH condition will requ...

Страница 259: ...d allow longer contact times Of course the RF field is limited by transmitter power and probe breakthrough limits Note the optimum power levels sp0 and pl1 and contact time p15 Setup of the Double CP...

Страница 260: ...er level for 15N channel NC contact pulse pl12 Power level decoupling f2 channel and excitation pl13 power level during second contact cw dec cnst24 offset for cw decoupling during p16 p3 Excitation p...

Страница 261: ...increased by 6 dB to get the same RF field as with a 100 square pulse 6 Usually the ramp shape is set on 13C but it can also be used on 15N Set pl5 to 46 or 24 kHz RF field on 15N Set spnam1 to ramp45...

Страница 262: ...tdisp select TanAmpMod as a shape model select solids notation select 1000 points set the spin rate to half the actual spin rate 5500 set the RF field to the actual RF field used on this channel selec...

Страница 263: ...compare the signal amplitude with the signal intensity of the 13 C CPMAS experiment with the same number of scans using dual display The intensity ratio of the aliphatic resonance of the CPMAS compar...

Страница 264: ...ampling windows 3 Re optimize the H N and N C HH conditions 4 Generate a new data set and switch to 2D data mode using the 123 icon in eda 5 In eda set the pulse program to doubcp Set FnMode as desire...

Страница 265: ...ffset depending on sample pl1 Power level for f1 channel NC contact pulse pl3 Power level for 15 N channel HN contact pl5 Power level for 15 N channel NC contact pulse pl12 Power level decoupling f2 c...

Страница 266: ...100 150 ppm Sweep width indirect dimension Table 20 3 Recommended Processing Parameters for the DCP 2D Parameter Value Comment F1 acquisition 13C left column si 2 4k FT size wdw QSINE Squared sine bel...

Страница 267: ...Double CP User Manual Version 002 BRUKER BIOSPIN 267 327 Example Spectra 20 5 Figure 20 8 C N correlation via Double CP in histidine simple setup sample 4mm Triple H C N Probe...

Страница 268: ...ith 22 ms DARR mixing period for C Cx spin diffusion on GB1 protein run using an EFREE Probe DARR transfer from C to C or Cx generates positive cross peaks HORROR or DREAM transfer generates negative...

Страница 269: ...mixing period for CaCx spin diffusion on GB1 protein run using an EFREE Probe at 14 kHz sample rotation and 100 kHz decoupling See the chapter on recoupling experiments for the SPC5 setup and for mor...

Страница 270: ...270 327 BRUKER BIOSPIN User Manual Version 002 Double CP...

Страница 271: ...Even spin rates in the order of 70 kHz which is no longer a mechani cal problem cannot fully average this interaction in rigid solids As chemical shift differences among the coupled nuclei become lar...

Страница 272: ...their applicability at limited spin rates because of the need for the cycle time to be short with respect to the rotor period often presents a problem References 1 S Hafner and H W Spiess Multiple Pul...

Страница 273: ...ndard procedure is to use quad detection and suppress the quad images by a suitable phase cycling scheme This is however not as straightforward as it is with standard excitation observation The quad p...

Страница 274: ...ion rate of the pulse sequence must be multiplied by this scal ing factor in order to place the resonances correctly This scaling factor can be calculated from the tilt angle but is also slightly depe...

Страница 275: ...equence is also very similar on AV3 instruments just different shapes and different timings are loaded Pulse Sequence Diagram of W PMLG or DUMBO 22 1 Figure 22 1 Pulse Sequence Diagram Table 22 1 Phas...

Страница 276: ...am dumbo Calling dumbo with xau dumbo will ask for the slice length of the shape usually 1 sec the number of slices usually 32 generate the shape and load the name of this shape into the current param...

Страница 277: ...own conversion is done without si multaneous digital filtering whereas the digital mode always down converts and filters simultaneously Remember that at a standard sampling rate of 20 MHz the fixed sa...

Страница 278: ...278 327 BRUKER BIOSPIN User Manual Version 002 CRAMPS 1D Analog Mode Sampling 22 3 1 Figure 22 4 Analog Sampling Scheme Digital Mode Sampling 22 3 2 Figure 22 5 Digital Sampling Scheme...

Страница 279: ...t which can easily be achieved with KBr on a double resonance probe or on BaClO3 H2O looking at the proton signal much like one does on the Br79 resonance Shimming will also be important since protons...

Страница 280: ...AV 3 instruments only pl12 sp1 for 100 kHz RF field up to 130 kHz To be optimized during setup spnam1 dumbo1_64 Set by xau dumbo p1 2 5 sec For 100 kHz RF field p8 1 2 sec p14 0 7 sec To be optimized...

Страница 281: ...ent in the solid state should be be low the 50 level Fine Tuning for Minimum Carrier Spike 22 7 The tilt pulse p14 and its phase cnst25 determine the size of the carrier spike Optimise both parameters...

Страница 282: ...scaling factor about 0 578 for WPMLG 0 47 for wpmlgd2 and 0 5 for DUMBO Some pulse programs are written such as to show the correct sweep width in ased which can then be set appropriately as s swh bef...

Страница 283: ...MPS 1D User Manual Version 002 BRUKER BIOSPIN 283 327 Figure 22 7 Optimizing cnst25 for Minimum Carrier Spike Optimized at 120 C Figure 22 8 Optimizing p14 for Minimum Carrier Spike Optimized at 0 6 s...

Страница 284: ...284 327 BRUKER BIOSPIN User Manual Version 002 CRAMPS 1D Figure 22 9 WPMLG CRAMPS After Optimization Digital Acquisition...

Страница 285: ...anymore This reduces setup time and enhances experimental possibilities significantly Reference 1 M Leskes P K Madhu and S Vega A broad banded z rotation windowed phase modulated Lee Goldburg pulse s...

Страница 286: ...hf DATE 2005 11 29 TIME 14 47 39 SHAPE_PARAMETERS MINX 1 000000E02 MAXX 1 000000E02 MINY 1 125000E01 MAXY 3 487500E02 SHAPE_EXMODE None SHAPE_TOTROT 0 000000E00 SHAPE_TYPE Excitation SHAPE_USER_DEF SH...

Страница 287: ...or PMLG and DUMBO 23 4 Table 23 2 PMLG Analog Mode Parameter Value Comment pulprog wpmlga2 Runs on AV 3 instruments only pl12 sp1 for 100 kHz RF field dto set cnst20 100 000 To be optimized during set...

Страница 288: ...factor of 0 47 Table 23 3 DUMBO Analog Mode Parameter Value Comment pulprog dumboa2 Runs on AV 3 instruments only pl12 sp1 For 100 kHz RF field up to 130 kHz To be optimized during setup spnam1 dumbo...

Страница 289: ...or must be done after acquisition changing the status parameter swh by typing s swh and dividing the value by the scaling factor about 0 47 for WPMLG and 0 5 for DUMBO Table 23 4 Parameters for Digita...

Страница 290: ...290 327 BRUKER BIOSPIN User Manual Version 002 Modified W PMLG...

Страница 291: ...ed in order to remove the carrier spike Without a carrier spike 2D experiments are much easier and faster to set up Being able to set the carrier close to the de sired spectral range one can make the...

Страница 292: ...ightly different from the windowed sequence so this needs to be adjusted separately Likewise decoupling during t1 could be imple mented using real frequency shifts as in the HETCOR sequence see Decou...

Страница 293: ...before transform as indicated above sw swh along F1 Same as for F2 Needs to be corrected before transform pulse pro gram calculates approximate values to be set before transform ased td 512 1k Dependi...

Страница 294: ...ent and strongly coupled The cross peaks at 3 and 4 ppm will show at a mixing time as short as 50 sec the cross peaks to the NH3 protons at 9 ppm require 200 300 sec to show The mixing time here was 5...

Страница 295: ...BIOSPIN 295 327 Figure 24 3 Spectrum of Tyrosine hydrochloride The mixing time was 300 sec to show all connectivities Full plot to show that smaller sweep widths can be chosen when the carrier can be...

Страница 296: ...of the Essential Part of the Spectrum Proton Proton DQ SQ Correlation 24 5 This experiment correlates proton shifts F2 with double quantum frequencies sum of shifts of the correlated sites Double qua...

Страница 297: ...e the shift range to be covered is small and the required power levels are easily achieved for protons Usually it is enough to calculate the required power level from the spin rate and the known proto...

Страница 298: ...tion cnst31 spin rate 10 15 000 Depending on available RF field l1 number of pc7 cycles 2 7 depending on dipolar coupling spnam1 m5m or m5p as in 1d setup DUMBO may be used with modified timing spnam2...

Страница 299: ...ue 0 6 After xfb the relative peak positions will be approxi mately correct but the absolute peak positions must be corrected by calibrating a known peak position to the correct value Examples 24 8 Th...

Страница 300: ...300 327 BRUKER BIOSPIN User Manual Version 002 CRAMPS 2D Figure 24 6 Glycine Proton Proton DQ SQ Correlation Using WPMLG in Both Directions...

Страница 301: ...CRAMPS 2D User Manual Version 002 BRUKER BIOSPIN 301 327 Figure 24 7 14 5 kHz W PMLG PC7 DQ SQ Correlation at 600 MHz with Ty rosine Hydrochloride...

Страница 302: ...302 327 BRUKER BIOSPIN User Manual Version 002 CRAMPS 2D...

Страница 303: ...he following page may be printed and filled out by every user using the instrument to trace eventual problems and provide information for the next us er Another copy may be printed for every user s ow...

Страница 304: ...304 327 BRUKER BIOSPIN User Manual Version 002...

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Страница 309: ...s are VTN Type Probes 28 Figure 3 17 WB Probes Eject Insert Connections 29 Figure 3 18 WB Probes DVT Probe Connections for RT and HT Measurements 29 Figure 3 19 SB VTN Probe MAS Connections 30 Figure...

Страница 310: ...pectrum of Adamantane at Moderate Spin Speed 68 Figure 4 13 Setting the Carrier on Resonance 69 Figure 4 14 Expanding the Region of Interest 70 Figure 4 15 Save Display Region to Menu 70 Figure 4 16 T...

Страница 311: ...10 RFDR 137 Figure 10 1 RFDR Pulse Sequence for 2D CPMAS Exchange Experiment 138 Figure 10 2 The 123 Icon in the Menu Bar of the Data Windows Acquisition Parameter Page 139 Figure 10 3 13C Histidine S...

Страница 312: ...ane Protein 200 16 Relaxation Measurements 201 Figure 16 1 The CPX T1 Pulse Sequence 203 Figure 16 2 Relaxation of Alpha carbon Signal in Glycine 207 17 Basic MQ MAS 213 Figure 17 1 A 3 Pulse Basic Se...

Страница 313: ...re 20 7 Double CP yield measured by comparing CPMAS and DCP amplitudes of the high field resonance 263 Figure 20 8 C N correlation via Double CP in histidine simple setup sample 4mm Triple H C N Probe...

Страница 314: ...295 Figure 24 4 Expansion of the Essential Part of the Spectrum 296 Figure 24 5 Pulse Sequence Diagram 297 Figure 24 6 Glycine Proton Proton DQ SQ Correlation Using WPMLG in Both Directions 300 Figure...

Страница 315: ...ments 105 Table 7 1 Acquisition Parameters 106 Table 7 2 Acquisition Parameters 107 Table 7 3 Acquisition Parameters 113 8 FSLG HETCOR 119 Table 8 1 Acquisition Parameters for FSLG HETCOR on tyrosine...

Страница 316: ...Parameters for the 1D CP Inversion Recovery Experiment 204 Table 16 2 Parameters for 2D Inversion Recovery Experiment 205 Table 16 3 Processing Parameters for CP T1 Relaxation Experiment 205 Table 16...

Страница 317: ...P 255 Table 20 1 Recommended Parameters for the DCP Setup 260 Table 20 2 Recommended Parameters for the DCP 2D Setup 265 Table 20 3 Recommended Processing Parameters for the DCP 2D 266 21 CRAMPS Gener...

Страница 318: ...318 327 BRUKER BIOSPIN User Manual Version 002 Tables...

Страница 319: ...amantane 11 12 ADP 103 AgNO3 13 AlPO 14 11 analog mode 277 Anatas 12 as hydroquinon 11 ased 60 AU program DUMBO 97 B B0 field 82 background signal 100 background suppression 100 BaClO3 H2O 279 Basic S...

Страница 320: ...ss polarisation 55 cross polarization under a LG frequency offset 119 Cu metal powder 11 CW decoupling 89 D D2O 12 d DMSO2 12 Default 58 dielectric loss 100 digital mode 277 d PE 12 dpl 70 d PMMA 12 d...

Страница 321: ...ng 89 Hg 12 Hg acetate 2 12 HH conditions 78 HH profile 78 high 66 High power decoupling 56 Homonuclear decoupling 92 Homonuclear dipolar interactions 271 HP HPPR modules 73 HPLNA 1H modules 73 I IN_F...

Страница 322: ...11 nonexponential decay 209 NQS 113 nrf 55 O observe nucleus 58 offset O1 58 oil free gas 56 optimize 71 optimum posmax 71 P Pb p tolyl 4 12 PbNO3 12 PCPD2 82 pcpd2 83 90 peakw 85 phase modulated pul...

Страница 323: ...formance 55 RF power 55 RF routing 55 S Sampling 277 saturation recovery 208 saturation recovery experiment 203 save button 71 Save Display Region to 70 SB probes 86 scaling factor 274 282 SELTICS 107...

Страница 324: ...ty compensated 74 SwitchF1 F2 66 T T1 99 202 T1 T2 relaxation 205 T1r 202 T1 99 T2 202 TI S 99 TMSS 12 Torchia method 203 TOSS 107 tp90 55 TPPM decoupling 90 transmitter 58 transverse magnetization 20...

Страница 325: ...Index User Manual Version 002 BRUKER BIOSPIN 325 327 Y Y NO3 3 6H2O 13 Z ZGoption Dlacq 75 ZGOPTNS 106 carbon at 43 ppm 80 glycine 12 79 glycine 79...

Страница 326: ...326 327 BRUKER BIOSPIN User Manual Version 002 Index...

Страница 327: ...User Manual Version 002 BRUKER BIOSPIN 327 327 End of Document...

Страница 328: ...solution package fromour comprehensive range or even collaborate with you on new developments Our ongoing efforts and considerable investment in research and development illustrates our long term comm...

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