Sigma-phase packing of icosahedral clusters in 780-atom tetragonal crystals of Cr5Ni3Si2 and V15Ni10Si that by twinning achieve 8-fold rotational point-group symmetry
AUTOR(ES)
Pauling, Linus
RESUMO
A 780-atom primitive tetragonal unit with edges 27.3, 27.3, and 12.6 Å is assigned to rapidly solidified Cu5Ni3Si2 and V15Ni10Si by analysis of electron diffraction photographs with the assumption that the crystals contain icosahedral clusters. There are thirty 26-atom clusters at the sigma-phase positions. Apparent 8-fold symmetry results from 45° twinning on the basal plane.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=279919Documentos Relacionados
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