Hi,
I've used to manage a Rigaku Ultima-III with a high temperature
attachment.
It takes about 30 minutes to mount and align. The alignment is
automatic, and very easy. Switching back to a standard stage
takes about the same time.
Data collection with the high temperature stage is slower than
with a standard stage because of the windows in the beam path.
I'm sure that's true for all the manufacturers.
The temperature stability seemed reasonable. At low temperatures,
(e.g 100C), the temperature would fluctuate by up to 5C. However,
at higher temperatures, the temperature didn't fluctuate by more than a
couple of degrees C (<1%) over a period of days. The thermocouples are
Pt, so thermocouple drift shouldn't be a problem. The drawback here
is
that the Rigaku software doesn't record the measured temperature as a
function of
time; you only get the temperature you set. The stability I'm
"quoting" is from
manual observations.
One warning about the Rigaku unit. The instructions tell you to drain
the
lines when you're not using it. That isn't suffiicient. You must
blow the
lines dry with nitrogen, or you'll get corrosion and have to send the
unit
back to Japan for repairs.
Overall we were pleased with the unit. ( I no longer work at the
institution
where I was responsible for the care and feeding of the instrument.)
David Lee, Ph.D.
DTLee Scientific, llc
dtlee.com
On Apr 20, 2009, at 8:38 AM, Leopoldo Suescun wrote:
Hi,
May I ask your help with this not specifically Rietveld-related
question?
I'm helping a colleague buy a new powder diffractometer with high
temperature attachment but I myself have little experience with this
particular attachment.
I'd appreciate if anyone could comment on the three most popular
Rigaku,
Panalytical and Bruker systems that offer these attachments. Mainly:
simplicity of operation/mounting, temperature stability, typical data
collection speeds (comparing Rietveld quality data in a typical range
20-120 with/without high-T chamber) and price/value relation.
He's on a hurry so comments are welcome and will be useful before
Wednesday.
Thanks in advance for your kind help.
Leo