2024/03/01 by Daniel Staško, Kristina Vlášková, Staško, Daniel +13
Chemistry · Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Nuclear materials and radiation effects #Radioactive element chemistry and processing #Strongly Correlated Electrons (cond-mat.str-el)
paper · pdf · doi:10.48550/arxiv.2403.00477
openalex publication_date 2024/03/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
A comprehensive study of the structural properties of the heavily investigated rare-earth A2Ir2O7 series under extreme conditions is presented. The series is covered by studying iridates with A = Pr, Sm, Dy-Lu. Temperature- and pressure-dependent synchrotron X-ray powder diffraction experiments reveal robustness of the pyrochlore structure throughout the rare-earth series, down to 4 K and up to 20 GPa. The thermal expansivity and pressure compressibility are determined, including Debye temperature, bulk modulus and Grüneisen parameter. Temperature and pressure evolution of the fractional coordinate of oxygen at 48f Wyckoff position, the sole free atomic position parameter, is investigated and discussed regarding the antiferromagnetic ordering of the Ir magnetic moments. In addition, the pressure evolution of the crystal structure of an IrO2 minority phase is followed. The tetragonal rutile-type structure is orthorhombically distorted at 15 GPa, and the orthorhombic structure is not fully stabilised up to 20 GPa.