With the addition of the new PheniX Cryostat to the PANalytical range of PreFIX tools, we have extended the non-ambient capabilities of the X’Pert PRO MPD diffractometer.
Fig. 1: The Oxford Phenix Cryostat on its PreFix interface
X-ray diffraction at non-ambient conditions is becoming a widely accepted technique thanks to our PreFIX stage interfacing and X’Celerator detector. The most recent addition to the non-ambient stages supported by PANalytical is the PheniX Cryostat (Figure 1) made by Oxford Cryosystems. With this new non-ambient chamber, powder diffractograms can now be recorded at temperatures down to 11 K, controlled with the X’Pert Data Collector software.
Cryostats have been used in combination with powder diffractometers for decades, but the large size of earlier models required special instruments dedicated to this task. The PheniX is a PreFIX sample stage that can easily be removed from the diffractometer, freeing the instrument for other tasks, and put back without the need for laborious reconnecting.
What’s more, the closed-cycle design, which removes the need for continuous supply of liquid helium, offers an important advantage by making the technique available to users without cryogenic experience.
We demonstrated the temperature accuracy of the PheniX by studying the temperature-dependent thermal expansion of aluminium, as well as the phase transition of TbVO4 at 33 K. Both studies confirmed the temperature accuracy of the PheniX. The phase-transition experiment also showed that interesting phenomena occur at these low temperatures (Figure 2), demonstrating the usefulness of this cryostat for materials research.
Results have been presented at two major X-ray diffraction conferences – the Denver X-ray Conference in August and the European Powder Diffraction Conference (EPDIC) in Prague in September 2004.
Fig. 2: Changes in the (Alpha2-stripped) patterns of TbVO4 as a function of temperature show that some reflections split up while others remain the same. The onset of the phase transition between 34 K and 32 K is consistent with the literature value.
This is an X'Press article. Please see the overview of all articles of this issue.
company