Order-disorder transition in Sr/sub 2/IrD/sub 5/: evidence for square pyramidal IrD/sub 5/ units from powder neutron diffraction data

Journal Article · Tue Dec 01 00:00:00 EST 1981 · J. Solid State Chem.; (United States)

DOI:https://doi.org/10.1016/0022-4596(81)90402-3· OSTI ID:5554332

Zhuang, J ^[1]; Hastings, J M; Corliss, L M; Bau, R; Wei, C Y; Moyer, Jr, R O

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1. Brookhaven National Lab., Upton, NY

Neutron diffraction data have been collected on a powdered sample of Sr/sub 2/IrD/sub 6/ over a range of temperatures. The compound, which is cubic at room temperature, has been found to exhibit a gradual transformation to a tetragonal phase in the temperature range 200 to 140 K. As a result of the transition, deuterium atoms which randomly occupy sixfold positions in the cubic phase, become tetragonally ordered. A small fraction of the cubic phase remained untransformed at 4.2 K. Both the cubic and tetragonal structures are consistent with square pyramidal IrD/sub 5/ units with average Ir-D distances of 1.714 and 1.718 A, respectively. Agreement factors, R/sub 1/, for the two structural analyses are 3.44 and 4.94%.

• OSTI ID: 5554332
• Journal Information: J. Solid State Chem.; (United States), Vol. 40:3
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
DEUTERIUM
ISOTOPE EFFECTS
IRIDIUM HYDRIDES
STRUCTURAL CHEMICAL ANALYSIS
STRONTIUM HYDRIDES
CRYSTAL STRUCTURE
CRYSTALLOGRAPHY
CUBIC LATTICES
DEUTERIUM COMPOUNDS
EXPERIMENTAL DATA
HYDRIDES
LOW TEMPERATURE
MEDIUM TEMPERATURE
MOLECULAR STRUCTURE
NEUTRON DIFFRACTION
PHASE TRANSFORMATIONS
POWDERS
TEMPERATURE DEPENDENCE
TETRAGONAL LATTICES
THERMODYNAMIC PROPERTIES
ULTRALOW TEMPERATURE
ALKALINE EARTH METAL COMPOUNDS
COHERENT SCATTERING
CRYSTAL LATTICES
DATA
DIFFRACTION
HYDROGEN COMPOUNDS
HYDROGEN ISOTOPES
INFORMATION
IRIDIUM COMPOUNDS
ISOTOPES
LIGHT NUCLEI
NUCLEI
NUMERICAL DATA
ODD-ODD NUCLEI
PHYSICAL PROPERTIES
SCATTERING
STABLE ISOTOPES
STRONTIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
360202* - Ceramics
Cermets
& Refractories- Structure & Phase Studies
400202 - Isotope Effects
Isotope Exchange
& Isotope Separation