TY  - JOUR
AU  - Wang, Bihan
AU  - Pakhomova, Anna
AU  - Khandarkhaeva, Saiana
AU  - Pillaca, Mirtha
AU  - Gille, Peter
AU  - Ren, Zhe
AU  - Lapkin, Dmitrii
AU  - Assalauova, Dameli
AU  - Alexeev, Pavel
AU  - Sergeev, Ilya
AU  - Kulkarni, Satishkumar
AU  - Weng, Tsu-Chien
AU  - Sprung, Michael
AU  - Liermann, Hanns-Peter
AU  - Vartaniants, Ivan
AU  - Glazyrin, Konstantin
TI  - Resolving the pressure induced ‘self-insertion’ in skutterudite CoSb3
JO  - Journal of alloys and compounds
VL  - 1017
SN  - 0925-8388
CY  - Lausanne
PB  - Elsevier
M1  - PUBDB-2024-05625
SP  - 179020
PY  - 2025
AB  - CoSb3 belongs to the skutterudite family of compounds and serves as a crucial platform for the exploration of thermoelectric materials. Under compression it undergoes a ‘self-insertion’ isostructural transition resulting in a peculiar redistribution of large Sb atoms between different crystallographic sites. We conducted a comprehensive investigation of CoSb3 structural phase stability up to 70 GPa using single crystal material in the regimes of conventional single crystal X-ray diffraction and the X-ray scattering focused on measuring Bragg peak at high resolution (including elements of Bragg Coherent Diffraction Imaging). We explore the compression behavior of CoSb3 in three different pressure transmitting media (PTM) and address several important topics: influence of various PTMs and nonhydrostatic stresses on the strongly correlated system of CoSb3, including the ‘self-insertion’ crossover, phase stability of CoSb3, the compound’s polymorphism, its crystal chemistry, and its variation under pressure. Among other important observations, we track population of Sb atom within CoSb3 dodecahedral sites on compression, during the process of ‘self-insertion’, and on decompression. We detect that ‘self-insertion’ may not only reduce the compressibility, but also make it negative. Finally, but not the least, we report that the ‘self-insertion’ crossover is an important step preceding a previously unknown phase transformation from a cubic Im3 ̅ CoSb3 into a trigonal R3 ̅ occurring above 40 GPa, and discuss the distinctive behavior of CoSb3 phases and their structural frameworks.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:001426750500001
DO  - DOI:10.1016/j.jallcom.2025.179020
UR  - https://bib-pubdb1.desy.de/record/613737
ER  -