Premium
The Structure, Characterization, and Magnetic Properties of Ca 4–x Ni x IrO 6 (x = 0.25, 0.5)
Author(s) -
Claridge John B.,
Layland Ralph C.,
Henley W. Hampton,
zur Loye HansConrad
Publication year - 1998
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/(sici)1521-3749(1998120)624:12<1951::aid-zaac1951>3.0.co;2-g
Subject(s) - crystallography , antiferromagnetism , octahedron , trigonal crystal system , crystal structure , materials science , rietveld refinement , chemistry , condensed matter physics , physics
Ca 4–x Ni x IrO 6 (x = 0.25, 0.5) crystallizes with trigonal (rhombohedral) symmetry in the space group R 3¯ c , Z = 6, for Ca 3.75 Ni 0.25 IrO 6 a = 9.3013(1) Å, c = 11.1554(1) Å; for Ca 3.5 Ni 0.5 IrO 6 a = 9.2723(1) Å, c = 11.0825(1) Å. Ca 3.75 Ni 0.25 IrO 6 and Ca 3.5 Ni 0.5 IrO 6 are isotypic to compounds of the Sr 4 PtO 6 structure type. The structure of Ca 3.75 Ni 0.25 IrO 6 has been solved by means of single crystal X‐ray diffraction data analysis with the reliability factors of R = 0.019 and R w = 0.022. Also, both structures have been determined by Rietveld refinement of powder X‐ray diffraction data. The structure consists of chains of alternating face‐sharing IrO 6 octahedra and (Ca/Ni)O 6 trigonal prisms. The chains are separated by the calcium cations which are in a distorted square antiprismatic coordination. Magnetic measurements revealed that both Ca 3.75 Ni 0.25 IrO 6 and Ca 3.5 Ni 0.5 IrO 6 follow Curie‐Weiss behavior at high temperatures. Ca 3.75 Ni 0.25 IrO 6 undergoes a single antiferromagnetic transition at T N = 5 K whereas Ca 3.5 Ni 0.5 IrO 6 undergoes two antiferromagnetic transitions at T N1 = 13 K and T N2 = 4 K.