Wombat - High-Intensity Powder Diffractometer
| Specifications Fact Sheet Applications Recent results Instrument Status Instrument Schedule |
|
Instrument scientists Note: Scientists from Echidna can Instrument Cabin Phone 9717 7032 |
Powder diffraction is a method in which Australia has long had significant strength. Materials with light elements in the presence of heavy ones (e.g. oxides, borides, carbides, etc.) can be measured with neutron powder diffraction, including magnetic materials. It is also very useful technique for bulk samples or experiments in extreme environments (pressure, temperature, stress, magnetic and electric fields or combinations thereof). It is good for multiphase materials and for quantitative phase analysis, in which the presence of minority materials can be measured accurately.
We have 2 world-class powder diffractometers: WOMBAT high-intensity powder diffractometer and ECHIDNA high-resolution powder diffractometer. WOMBAT is optimised for kinetics experiments and very small samples, and will be our highest performance instrument. WOMBAT will likely attract usage from around the world, and will specialise on in-situ studies of chemical reactions, other dynamic phenomena, high-pressure experiments and magnetism. The high performance comes from the combination of the best area detector ever constructed for neutron diffraction with the largest beam guide yet put into any research reactor and a correspondingly large crystal monochromator. It is difficult to predict where major materials discoveries will take place in the future, but future scientific opportunities will likely include: novel hydrogen-storage materials, negative-thermal-expansion materials, methane-ice clathrates, pharmaceutical molecules, and materials for fusion reactors, to name but a few.
The mission for WOMBAT is to provide scientists with a high-intensity diffractometer at the OPAL reactor which can be used to carry out high-impact science in cases where
-
the sample specimens are small (~10mg)
-
the samples are contained in complex sample environment(s), for example in pressure cells
-
rapid real time measurements are required to determine crystal structures quickly for phase transitions, chemical reactions and kinetic studies
-
stroboscopic measurements are required on timescales down to 30µs
The method for achieving this is to build a flexible modular instrument which can exploit the advantages of (i) focussing neutron optics in the monochromator system over a wide range of incident wavelengths, (ii) a large solid angle detector with position sensitive detection capabilities, (iii) an advanced data acquisition electronics and (iv) a re-configurable collimation system which optimises the background reduction in each experiment.