Electron-poor SrAu{sub x}In{sub 4-x} (0.5{<=}x{<=}1.2) and SrAu{sub x}Sn{sub 4-x} (1.3{<=}x{<=}2.2) phases with the BaAl{sub 4}-type structure

Journal Article · Wed Aug 15 04:00:00 EDT 2007 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2007.06.004· OSTI ID:21043807

Tkachuk, Andriy V ^[1]; Mar, Arthur ^[1]

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1. Department of Chemistry, University of Alberta, Edmonton, Alta., T6G 2G2 (Canada)

Solid solutions SrAu{sub x}In{sub 4-x} (0.5{<=}x{<=}1.2) and SrAu{sub x}Sn{sub 4-x} (1.3{<=}x{<=}2.2) have been prepared at 700 deg. C and their structures characterized by powder and single-crystal X-ray diffraction. They adopt the tetragonal BaAl{sub 4}-type structure (space group I4/mmm, Z=2; SrAu{sub 1.1(1)}In{sub 2.9(1)}, a=4.5841(2) A, c=12.3725(5) A; SrAu{sub 1.4(1)}Sn{sub 2.6(1)}, a=4.6447(7) A, c=11.403(2) A), with Au atoms preferentially substituting into the apical over basal sites within the anionic network. The phase width inherent in these solid solutions implies that the BaAl{sub 4}-type structure can be stabilized over a range of valence electron counts (vec), 13.0-11.6 for SrAu{sub x}In{sub 4-x} and 14.1-11.4 for SrAu{sub x}Sn{sub 4-x}. They represent new examples of electron-poor BaAl{sub 4}-type compounds, which generally have a vec of 14. Band structure calculations confirm that substitution of Au, with its smaller size and fewer number of valence electrons, for In or Sn atoms enables the BaAl{sub 4}-type structure to be stabilized in the parent binaries SrIn{sub 4} and SrSn{sub 4}, which adopt different structure types. - Graphical abstract: BaAl{sub 4}-type structure of solid solutions SrAu{sub x}In{sub 4-x} (0.5{<=}x{<=}1.2) and SrAu{sub x}Sn{sub 4-x} (1.3{<=}x{<=}2.2), with apical sites preferentially occupied by Au atoms.

• OSTI ID: 21043807
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 8 Vol. 180; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
GOLD
GOLD ALLOYS
INDIUM ALLOYS
INTERMETALLIC COMPOUNDS
MONOCRYSTALS
SOLID SOLUTIONS
SPACE GROUPS
STRONTIUM ALLOYS
TETRAGONAL LATTICES
TIN ALLOYS
X-RAY DIFFRACTION