Anton Paar TTK 600, Reference Manual

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5 Putting TTK 600 into Operation
D52IB001EN-G 35
5.1.2 Height Alignment with Motorized Align-
ment Stage
Motorized alignment stages are remote controlled.
The height (z-position) of TTK 600 can be adjusted
from outside the diffractometer enclosure.
• The sample height can be aligned while the X-
ray beam is on.
• The sample height can be re-aligned during the
experiment at any temperature.
• The alignment stage offers an accuracy of
< 5 µm.
• Digital display of the chamber position is possi-
ble.
For information about the operation of the motorized
alignment stage, read the instruction manual of the
alignment stage.
5.1.3 Alignment of the Chamber Rotation
The TTK 600 chamber must be aligned on the goni-
ometer so that the sample holder surface is parallel
to the
Θ -zero line of the diffractometer ( ω -align-
ment).
The procedure for rotating TTK 600 relative to the
goniometer depends on the type of diffractometer.
Refer to the instruction manual for the diffractometer
for details.
If the chamber is rotated too much relative to the Θ -
zero line of the diffractometer, the X-ray beam will
not pass through the alignment slit. Therefore start
the alignment of the chamber rotation with the stan-
dard sample holder mounted in the chamber
(coarse alignment).
When the chamber is roughly aligned parallel to the
Θ -zero line, replace the standard sample holder with
the alignment block and repeat the procedure.
5.2 Alignment of the Standard Sample
Holder
Carry out the alignment as follows:
1. Put an appropriate beam attenuator in the pri-
mary beam path.
2. Generate a narrow X-ray beam (small beam
height) and select a detector area which is
larger than the beam.
3. Set the goniometer to Θ = 0° / 2 Θ = 0°.
4. Move the chamber to the Θ -zero line as follows:
If you have mounted the standard sample
holder:
• Lower the chamber until no parts are in the X-
ray beam path and determine the maximum
beam intensity I
max
.
• Lift the chamber until the X-ray beam is com-
pletely blocked and determine the background
intensity I
bg
.
• Move the chamber down until the beam intensity
I = ½ · (I
max
- I
bg
), which means that the upper
edge of the alignment block bisects the X-ray
beam.
If you have mounted the alignment block:
• Move the chamber up and down until the X-ray
beam passes through the alignment slit with
maximum intensity I
max
.
5. Carry out an ω -scan and measure the beam
intensity. Determine the ω -offset of the maxi-
mum of the intensity profile.
TIP:
For Θ - Θ diffractometers, rotate
detector around the center axis of the go-
niometer.
For
Θ -2 Θ diffractometers, rotate the chamber
around the center axis of the goniometer.
When starting with the ω -alignment, do the ω -scan
with ±3°. As the alignment gets better, reduce the
scan range.
6. Depending on the ω -offset ( ∆ω ), rotate the
chamber as described in the instruction manual
for the diffractometer:
ω -offset negative (-) - rotate clockwise
ω -offset positive (+) - rotate anti-clockwise
7. Fix the chamber on the goniometer.
8. Set the goniometer back to Θ = ω = 2 Θ = 0°
and re-align the chamber height (z-position) as
described in step 4.
NOTICE
Risk of damage.
The procedure described in this section requires
that the detector is moved into the primary X-ray
beam. Always use an appropriate beam attenua-
tor and read the relevant sections in the instruc-
tion manual for the diffractometer before you
start the alignment.