Premium
A New Structure Type for Rare‐Earth‐Metal Cluster Compounds stabilized by transition metals: KPr 6 I 10 Os, CsPr 6 I 10 Fe, CsLa 6 I 10 Fe, and CsLa 6 I 10 Mn
Author(s) -
Lulei Michael,
Corbett John D.
Publication year - 1996
Publication title -
zeitschrift für anorganische und allgemeine chemie
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.354
H-Index - 66
eISSN - 1521-3749
pISSN - 0044-2313
DOI - 10.1002/zaac.19966221009
Subject(s) - isostructural , crystallography , triclinic crystal system , octahedron , orthorhombic crystal system , transition metal , cluster (spacecraft) , crystal structure , chemistry , metal , halide , atom (system on chip) , inorganic chemistry , biochemistry , organic chemistry , computer science , programming language , embedded system , catalysis
Abstract Reactions of KI, Pr, PrI 3 , and Os in niobium tubes at 800° yielded black, air‐ and moisture‐sensitive crystals of Kpr 6 I 10 Os which were characterized by single crystal X‐ray diffraction (orthorhombic, Pnma, a = 15.362(3), b = 13.498(2), c = 14.128(3) Å, Z = 4, R(F)/R w = 4.4/5.6%). Subsequent parallel experiments also gave, according to Guinier powder pattern data, the isostructural compounds CsPr 6 I 10 Fe ( a = 15.312(2), b = 13.426(1), c = 14.154(1) Å), CsLa 6 I 10 Fe ( a = 15.523(2), b = 13.646(2), c = 14.334(1) Å) and CsLa 6 I 10 Mn ( a = 15.457(4), b = 13.737(2), c = 14.329(2) Å). The important structural feature is the presence of octahedral rare‐earth‐metal cluster units R 6 that are centered by a transition‐metal atom Z and bridged and interconnected by halide atoms. The new compounds exhibit the same general pattern of halide connectivity (R 6 Z)X 2 i X 4/2 i–i X 6/2 i–a X 6/2 a–ias do the triclinic compounds R 6 X 10 Z. However, the structural arrangement of the metal octahedra is significantly different; they are linked by I i–i atoms into zigzag chains along [010] and these are interconnected into a three dimensional network by I i–a atoms to form channels in which the alkali‐metal atoms are located. The introduction of alkali‐metal atoms into reactions leads to new quaternary compounds with discrete rare‐earth‐metal clusters centered by transition metals and more open structure frameworks. Measurements of the temperature dependencies of the magnetic susceptibilities for CsLa 6 I 10 Fe and CsLa 6 I 10 Mn are consistent with expectations for 17‐ and 16‐electron cluster systems, respectively.