2023/06/30 by Thomas Doert, Hagen Poddig, Kati Finzel
Chemistry · Materials Science · #Crystal Structures and Properties #Inorganic Chemistry and Materials #Solid-state spectroscopy and crystallography
paper · doi:10.1002/zaac.202300118
openalex publication_date 2023/06/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Abstract Polychalcogenides REX 2‐δ ( X =S, Se, Te; 0≤ δ ≤0.2) of trivalent rare earth metals RE have been investigated in recent years to shed light on the structural diversity as a function of compositional, metric, thermodynamic, and electronic situation. Whereas the former aspects have comparable influence on the structures of all polychalcogenides REX 2‐δ , the bonding situation was assumed different for tellurides due to tellurium's higher tendency to delocalize electrons. The crystal structures generally contain puckered [ REX ] double slabs and planar [ X ] layers, the latter hosting different distortions from a square‐like arrangement. The distortion patterns of sulfides and selenides can be understood by a Zintl‐type approach; they are dominated by localization of valence electrons in mono‐ ( X 2− ) or dinuclear ( X 2 2− ) anions only. This review discusses crystal structures of some rare‐earth metal polytellurides RE Te 2‐δ (0≤ δ ≤0.2) and bonding features in the chalcogenide layers and relates them to their sulfide and selenide counterparts.