Campus Units

Ames Laboratory, Chemistry

Document Type

Article

Publication Version

Published Version

Publication Date

2007

Journal or Book Title

Inorganic Chemistry

Volume

46

Issue

1

First Page

251

Last Page

260

DOI

10.1021/ic0616380

Abstract

The crystal structures, atomic distributions, and theoretical electronic structures of five different Cu5-xZn8+x γ-brass compounds (x = −0.59(3), −0.31(3), 0.00(3), 0.44(3), and 0.79(3)) are reported with the goal of identifying chemical influences on the observed phase width. These structures have been refined by both neutron and X-ray powder diffraction to obtain accurate crystal chemical parameters. All compounds crystallize in the space group I4̄3m (No. 217) (Z = 4), and the unit cell parameters are a = 8.8565(4), 8.8612(5), 8.8664(3) , 8.8745(4), and 8.8829(7) Å, respectively, for Cu5.59Zn7.41, Cu5.31Zn7.69, Cu5.00Zn8.00, Cu4.56Zn8.44, and Cu4.21Zn8.79. The results indicate specific site substitutions on both sides of the ideal composition “Cu5Zn8”. In all cases, the 26-atom cluster building up the γ-brass structure shows a constant inner [Cu4Zn4] tetrahedral star with compositional variation occurring at the outer octahedron and cuboctahedron. First principles and semiempirical electronic structure calculations using both a COHP and Mulliken population analysis were performed to understand the observed compositional range and to address the “coloring problem” for the site preferences of Cu and Zn atoms for this series of compounds.

Comments

Reprinted (adapted) with permission from Inorg. Chem., 2007, 46 (1), pp 251–260. Copyright 2007 American Chemical Society.

Copyright Owner

American Chemical Society

Language

en

File Format

application/pdf

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