Campus Units

Ames Laboratory, Chemistry

Document Type

Article

Publication Version

Published Version

Publication Date

2006

Journal or Book Title

Chemistry of Materials

Volume

18

Issue

3

First Page

822

Last Page

831

DOI

10.1021/cm0515505

Abstract

Composition, crystal structures, polymorphic transformations, and stability of the thermoelectric material known in the literature as “Zn4Sb3” have been studied on a polycrystalline sample and Bi-flux-grown single crystals using X-ray diffraction techniques, resistance, and Seebeck coefficient measurements at various temperatures ranging from 4 to 773 K. Microprobe analysis yields the composition of the flux-grown crystals to be close to Zn13Sb10, with minor Bi doping. High-temperature X-ray and Seebeck coefficient studies show that the phase is unstable at high temperatures in a vacuum because of Zn losses. Both X-ray diffraction and resistivity measurements indicate the presence of two consecutive symmetry-breaking transitions below room temperature, in agreement with our previous results on polycrystalline samples. Application of Landau theory suggests that the first Rc C2/c symmetry breaking may be second-order in nature. The second, low-temperature symmetry breaking may proceed along two routes. One of these pathways, a first-order C2/c C1 symmetry reduction, may lead to an incommensurate structure and is consistent with our experimental observations.

Comments

Reprinted (adapted) with permission from Chem. Mater., 2006, 18 (3), pp 822–831. Copyright 2006 American Chemical Society.

Copyright Owner

American Chemical Society

Language

en

File Format

application/pdf

Share

COinS