Compression mechanisms of symmetric and Jahn-Teller distorted octahedra in double perovskites: A {sub 2}CuWO{sub 6} (A=Sr, Ba), Sr{sub 2}CoMoO{sub 6}, and La{sub 2}LiRuO{sub 6}

Journal Article · Wed Nov 15 00:00:00 EST 2006 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2006.07.016· OSTI ID:20900896

Lufaso, Michael W ^[1]; Gemmill, William R ^[1]; Mugavero, Samuel J ^[1]; Lee, Yongjae ^[2]; Vogt, Thomas ^[1]; Loye, Hans-Conrad zur ^[1]

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1. Department of Chemistry and Biochemistry, University of South Carolina, 631 Sumter Street, Columbia, SC 29208 (United States)
2. Department of Earth System Sciences, Yonsei University, Seoul 120749 (Korea, Republic of)

Synchrotron X-ray powder diffraction was used to study the high pressure dependence of the lattice parameter and structural evolution of the monoclinic La{sub 2}LiRuO{sub 6} and tetragonal Sr{sub 2}CoMoO{sub 6}, Sr{sub 2}CuWO{sub 6}, and Ba{sub 2}CuWO{sub 6} double perovskite phases. The c lattice parameters of Sr{sub 2}CuWO{sub 6} and Ba{sub 2}CuWO{sub 6} decreased more rapidly than the a lattice parameters and Ba{sub 2}CuWO{sub 6} exhibited a more anisotropic compression compared to Sr{sub 2}CuWO{sub 6}. Based on lower pressure refinements of Ba{sub 2}CuWO{sub 6}, the anisotropic compression is proposed to be due to the preferential compression of the Cu-O bonds containing cooperative Jahn-Teller distortions aligned parallel to the c-axis, which is in contrast to Sr{sub 2}CoMoO{sub 6}, where the change in the octahedral tilting and symmetric bond compression is the prevailing compression mechanism. The bulk moduli were obtained from a fit of the volume-pressure data using the second-order Murnaghan equation of state. - Graphical abstract: Preferential compression of long Cu-O bonds, resulting from Jahn-Taller distortions aligned parallel to the c-axis, is observed for Ba{sub 2}CuWO{sub 6}. This in cast to the compression mechanism often observed in perovskites, i.e. octahedral tilting and symmetric octahedral bond compression.

• OSTI ID: 20900896
• Journal Information: Journal of Solid State Chemistry, Vol. 179, Issue 11; Other Information: DOI: 10.1016/j.jssc.2006.07.016; PII: S0022-4596(06)00399-9; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANISOTROPY
BARIUM COMPOUNDS
COBALT COMPOUNDS
COMPRESSION
EQUATIONS OF STATE
LANTHANUM COMPOUNDS
LATTICE PARAMETERS
LITHIUM COMPOUNDS
MOLYBDATES
MONOCLINIC LATTICES
OXYGEN COMPOUNDS
PEROVSKITE
RUTHENIUM COMPOUNDS
STRONTIUM COMPOUNDS
SYNCHROTRON RADIATION
TUNGSTATES
X-RAY DIFFRACTION