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Title: Zn13(CrxAl1-x)27 (x = 0.34-0.37): a new intermetallic phase containing icosahedra as building units

Abstract

The title compounds Zn{sub 13}(Cr{sub x}Al{sub 1-x}){sub 27} (x = 0.34-0.37) were obtained by melting the pure elements at 923 K, and followed by a heat treatment at 723 K in a tantalum container. According to single crystal structural analysis, the title compounds crystallize in the rhombohedral system, adopting a new structure type (R-3m, a = 7.5971(8), c = 36.816(6), for crystal I). Single crystal X-ray structural analysis reveals a statistical mixing of Cr/Al in their crystallographic positions. Single crystal and powder X-ray diffraction as well as energy dispersive X-ray analyses suggested the title phase to have a narrow homogeneity range. The substructure of Zn{sub 13}(Cr{sub x}Al{sub 1-x}){sub 27} shows close resemblance with the Mn{sub 3}Al{sub 10} structure type. A bonding analysis, through crystal orbital Hamiltonian populations (COHPs), of 'Cr{sub 9}Al{sub 18}Zn{sub 13}' as a representative composition indicated that both homo- and heteronuclear interactions are important for the stability of this new phase.

Authors:
; ;
Publication Date:
Research Org.:
Ames Laboratory (AMES), Ames, IA (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1025606
Report Number(s):
IS-J 7617
Journal ID: 0044-2968; TRN: US201120%%724
DOE Contract Number:
DE-AC02-07CH11358
Resource Type:
Journal Article
Resource Relation:
Journal Name: Zeitschrift fuer Kristallographie; Journal Volume: 226; Journal Issue: 7
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 36 MATERIALS SCIENCE; BONDING; DIFFRACTION; HAMILTONIANS; HEAT TREATMENTS; INTERMETALLIC COMPOUNDS; MELTING; MONOCRYSTALS; STABILITY; TANTALUM; X-RAY DIFFRACTION

Citation Formats

Thimmaiah, Srinivasa, Han, Mi-Kyung, and Miller, Gordon J. Zn13(CrxAl1-x)27 (x = 0.34-0.37): a new intermetallic phase containing icosahedra as building units. United States: N. p., 2011. Web. doi:10.1524/zkri.2011.1376.
Thimmaiah, Srinivasa, Han, Mi-Kyung, & Miller, Gordon J. Zn13(CrxAl1-x)27 (x = 0.34-0.37): a new intermetallic phase containing icosahedra as building units. United States. doi:10.1524/zkri.2011.1376.
Thimmaiah, Srinivasa, Han, Mi-Kyung, and Miller, Gordon J. 2011. "Zn13(CrxAl1-x)27 (x = 0.34-0.37): a new intermetallic phase containing icosahedra as building units". United States. doi:10.1524/zkri.2011.1376.
@article{osti_1025606,
title = {Zn13(CrxAl1-x)27 (x = 0.34-0.37): a new intermetallic phase containing icosahedra as building units},
author = {Thimmaiah, Srinivasa and Han, Mi-Kyung and Miller, Gordon J.},
abstractNote = {The title compounds Zn{sub 13}(Cr{sub x}Al{sub 1-x}){sub 27} (x = 0.34-0.37) were obtained by melting the pure elements at 923 K, and followed by a heat treatment at 723 K in a tantalum container. According to single crystal structural analysis, the title compounds crystallize in the rhombohedral system, adopting a new structure type (R-3m, a = 7.5971(8), c = 36.816(6), for crystal I). Single crystal X-ray structural analysis reveals a statistical mixing of Cr/Al in their crystallographic positions. Single crystal and powder X-ray diffraction as well as energy dispersive X-ray analyses suggested the title phase to have a narrow homogeneity range. The substructure of Zn{sub 13}(Cr{sub x}Al{sub 1-x}){sub 27} shows close resemblance with the Mn{sub 3}Al{sub 10} structure type. A bonding analysis, through crystal orbital Hamiltonian populations (COHPs), of 'Cr{sub 9}Al{sub 18}Zn{sub 13}' as a representative composition indicated that both homo- and heteronuclear interactions are important for the stability of this new phase.},
doi = {10.1524/zkri.2011.1376},
journal = {Zeitschrift fuer Kristallographie},
number = 7,
volume = 226,
place = {United States},
year = 2011,
month = 3
}
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