The classification of structural phase transitions as displacive or order-disorder in character is usually based on spectroscopic data above the transition. We use single crystal x-ray diffraction to investigate structural correlations in the quasi-skutterudites, (CaxSr1−x)3Rh4Sn13, which have a quantum phase transition at x∼0.9. Three-dimensional pair distribution functions show that the amplitudes of local atomic displacements are temperature-independent below the transition and persist to well above the transition, a signature of order-disorder behavior. The implications for the associated electronic transitions are discussed.
@article{arxiv.2205.02305,
title = {Order-Disorder Transitions in (Ca$_x$Sr$_{1-x}$)$_3$Rh$_4$Sn$_{13}$},
author = {Puspa Upreti and Matthew Krogstad and Charlotte Haley and Mihai Anitescu and Vishwas Rao and Lekh Poudel and Omar Chmaissem and Stephan Rosenkranz and Raymond Osborn},
journal= {arXiv preprint arXiv:2205.02305},
year = {2022}
}