2013/08/01 by K. R. Knox, Kevin R. Knox, Milinda Abeykoon +11
Chemistry · Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Chemistry #Condensed matter physics #Crystallography #Materials science #Nuclear materials and radiation effects #Phase (matter) #Phase transition #Physics #Pyrochlore #Quantum mechanics #Spinel #X-ray Diffraction in Crystallography #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.88.174114
published as Phys. Rev. B 88, 174114 (2013)
arxiv created 2013/08/01 · openalex publication_date 2013/11/25 · arxiv updated 2013/12/10 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The local structure of the spinel LiRh2O4 has been studied using atomic-pair distribution function analysis of powder x-ray diffraction data. This measurement is sensitive to the presence of short Rh-Rh bonds that form due to dimerization of Rh4+ ions on the pyrochlore sublattice, independent of the existence of long-range order. We show that structural dimers exist in the low-temperature phase, as previously supposed, with a bond shortening of \ensuremathΔr\ensuremath∼0.15 \AA. The dimers persist up to 350 K, well above the insulator-metal transition, with \ensuremathΔr decreasing in magnitude on warming. Such behavior is inconsistent with the Fermi-surface nesting-driven Peierls transition model. Instead, we argue that LiRh2O4 should properly be described as a strongly correlated system.