Properties of the transition metal dichalcogenides: The case of IrS sub 2 and IrSe sub 2

Journal Article · Fri Nov 30 23:00:00 EST 1990 · Journal of Solid State Chemistry; (USA)

DOI:https://doi.org/10.1016/0022-4596(90)90273-Z· OSTI ID:6013352

Jobic, S; Deniard, P; Brec, R; Rouxel, J ^[1]; Drew, M G.B. ^[2]; David, W I.F. ^[3]

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1. Institut de Physique et Chimie des Materiaux, Nantes (France)
2. The University, Reading (England)
3. Rutherford Appleton Laboratory, Didcot (England)

The syntheses and structure determination of IrSe{sub 2} and IrS{sub 2} were undertaken. Pure phases were obtained and powder data were measured on an X-ray diffractometer. Rietveld refinement was successfully carried out for both structures (IrSe{sub 2}, 269 observations R (weighted profile) 0.062; IrS{sub 2}, 205 observations R (weighted profile) 0.074). The Pnam space group (No. 62) was found to yield the best results, eliminating Pna2{sub 1} as the other possible space group considered in a previous study of IrSe{sub 2}. Chalcogen pairs are found in both structures and these may correspond, in a first approach, to the charge balance Ir{sup 3+}X{sup 2{minus}}(X{sub 2}){sup 2{minus}}{sub 1/2}. However, long bond lengths were found in the chalcogen pairs (S-S 2.299(11) {angstrom}, Se-Se 2.555(4) {angstrom}) along with an unexpectedly small effective cationic radius of 0.50 {angstrom} for Ir{sup 3+}. These features of IrS{sub 2} and IrSe{sub 2} are discussed.

• OSTI ID: 6013352
• Journal Information: Journal of Solid State Chemistry; (USA), Journal Name: Journal of Solid State Chemistry; (USA) Vol. 89:2; ISSN JSSCB; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360601* -- Other Materials-- Preparation & Manufacture
360602 -- Other Materials-- Structure & Phase Studies
CHALCOGENIDES
CHEMICAL PREPARATION
COHERENT SCATTERING
CRYSTAL STRUCTURE
DATA
DIFFRACTION
EXPERIMENTAL DATA
INFORMATION
IRIDIUM COMPOUNDS
LATTICE PARAMETERS
MEASURING METHODS
NUMERICAL DATA
REFRACTORY METAL COMPOUNDS
SCATTERING
SPACE GROUPS
SULFIDES
SULFUR COMPOUNDS
SYNTHESIS
TRANSITION ELEMENT COMPOUNDS
X-RAY DIFFRACTION