Variable temperature and pressure studies of new zero thermal expansion materials

We have recently expanded the Sc2-xAlxW3O12 series of materials to include the Sc2-x-yAlxFeyW3O12 series. In the latter series, we have found a subset of materials that exhibit zero thermal expansion. These have been thoroughly characterised using variable temperature synchrotron XRD and neutron powder diffraction (ANSTO) and high pressure neutron diffraction (ANSTO). Our next objective is to undertake variable temperature and high pressure (VTHP) neutron diffraction studies on two compositions that exhibit zero thermal expansion.
This will build on our recently completed VTHP experiments on the ambient pressure zero thermal expansion material, Sc1.5Al0.5W3O12, July 2024 where we were able to build a pressure-temperature phase diagram and determine the coefficients of thermal expansion at various pressures in different crystal structures. We propose to undertake an analogous series of experiments but here we would target not only one composition but multiple compositions that result in zero thermal expansion at ambient pressure. This would allow us to build a composition-pressure-temperature phase diagram. In addition, neutrons would be ideal for this as we would also determine the atomic scale perturbations of these materials under pressure which is difficult because it contains oxygen.