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BRUKER BIOSPIN
User Manual Version 002
Symmetry Based Recoupling
Running the experiment on enriched
15
N samples is of course possible, but one
should consider that most samples will not have nitrogen atoms directly attached
to each other, so small couplings will prevail, requiring long DQ-excitation and -re-
conversion times, with a nucleus that requires high RF power levels to achieve a
certain RF-field. On the other side, the shift range is not large, allowing relatively
slow spinning. Considering a nucleus like
31
P, there is no need for enrichment, but
cases with directly bonded
31
P-atoms are rare. Phosphates are usually easy,
since the shift range is small (couplings are also rather small). If however a large
shift range (possible with
31
P) needs to be covered, there may be a substantial
problem.
1. C7 is not recommended due to restricted excitation bandwidth.
2. SPC5 can be recommended as a standard sequence for 4mm probes 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 fields taken from
13
C RF field specification, or
1
H RF field
specification, considering the requirement of an off HH condition.
6. Maximum RF field for decoupling
7. +LG means cw decoupling with optimized LG-offset frequency at the given RF
field in order to avoid HH contact.
Table 14.1.
Recommended Probe/Spin Rates for Different Experiments and Magnetic Field Strengths
Sequence
n=
(
ν
RF
/
masr)
rotor
diameter/
masr
max.
masr
max.
rec.
4
(Hz)
ν
RF
(
13
C) max.
(kHz/
μ
s)
5
ν
RF
(H) max.
(kHz/
μ
s)
6
B
o
max.
(MHz)
8
POST-C7
1
7
7/6000
5000
35 / 7.15
70 / 3.5 +LG
300
4/15000
9000
63 / 4
100 / 2.5 +LG
7
500
3.2/24000
12000
84 / 3
110 / 2.27 +LG
7
600
2.5/35000
14000
100 / 2.5
130 / 1.95 +LG
7
800
SPC5
2
5
7/6000
5000
25 / 10
70 / 3.5
300
4/15000
13000
65 / 3.85
100 / 2.5 +LG
7
500
3.2/24000
17000
85 / 3
none
700
2.5/35000
20000
100 / 2.5
none
900
SC14
3
3.5
7/6000
6000
21 / 12
70 / 3.5
200
4/15000
15000
52.5 / 4.75
100 / 2.5 +LG
7
500
3.2/24000
22000
77 / 3.25
none
700
2.5/35000
28000
100 / 2.5
none
950
Содержание Solid State NMR
Страница 1: ...Version Bruker BioSpin think forward NMR Spectroscopy Solid State NMR 002 AVANCE Solids User Manual...
Страница 8: ...8 BRUKER BIOSPIN User Manual Version 002 Contents...
Страница 14: ...14 327 BRUKER BIOSPIN User Manual Version 002 Test Samples...
Страница 104: ...104 327 BRUKER BIOSPIN User Manual Version 002 Practical CP MAS Spectroscopy on Spin 1 2 Nuclei...
Страница 118: ...118 327 BRUKER BIOSPIN User Manual Version 002 Basic CP MAS Experiments...
Страница 122: ...122 327 BRUKER BIOSPIN User Manual Version 002 FSLG HETCOR Figure 8 3 The ased Display...
Страница 154: ...154 327 BRUKER BIOSPIN User Manual Version 002 Proton Driven Spin Diffusion PDSD...
Страница 172: ...172 327 BRUKER BIOSPIN User Manual Version 002 SUPER Figure 13 3 The Acquisition Parameter Window eda...
Страница 178: ...178 327 BRUKER BIOSPIN User Manual Version 002 SUPER...
Страница 192: ...192 327 BRUKER BIOSPIN User Manual Version 002 Symmetry Based Recoupling...
Страница 212: ...212 327 BRUKER BIOSPIN User Manual Version 002 Relaxation Measurements...
Страница 270: ...270 327 BRUKER BIOSPIN User Manual Version 002 Double CP...
Страница 284: ...284 327 BRUKER BIOSPIN User Manual Version 002 CRAMPS 1D Figure 22 9 WPMLG CRAMPS After Optimization Digital Acquisition...
Страница 290: ...290 327 BRUKER BIOSPIN User Manual Version 002 Modified W PMLG...
Страница 302: ...302 327 BRUKER BIOSPIN User Manual Version 002 CRAMPS 2D...
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Страница 318: ...318 327 BRUKER BIOSPIN User Manual Version 002 Tables...
Страница 326: ...326 327 BRUKER BIOSPIN User Manual Version 002 Index...
Страница 327: ...User Manual Version 002 BRUKER BIOSPIN 327 327 End of Document...