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Title: Preparation of CoGe 2 -type NiSn 2 at 10 GPa
Abstract An unprecedented NiSn 2 intermetallic with CoGe 2 -type crystal structure has been recovered (at ambient conditions) after high-pressure high-temperature treatment of a Ni 33 Sn 67 precursor alloy at 10 GPa and 400 °C. The orthorhombic structure with Aeam space group symmetry is pseudotetragonal. Based on the evaluation of powder X-ray diffraction data, lattice parameters of a  =  b  = 6.2818 Å and c  = 11.8960 Å have been determined. Complicated line broadening and results of a further microstructure analysis, however, imply a defective character of the crystal structure. First-principles calculations with different model structures and a comparison with structural trends in the literature suggest that at the high-pressure high-temperature conditions a CuAl 2 -type crystal structure might be stable, which transforms to the recovered CoGe 2 -type crystal structure upon cooling or the release of pressure.
Authors:
; ; ; ;
Award ID(s):
1825538
Publication Date:
NSF-PAR ID:
10299692
Journal Name:
Zeitschrift für Naturforschung B
Volume:
0
Issue:
0
ISSN:
0932-0776
Sponsoring Org:
National Science Foundation
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