Skip to main content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.


The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

The Local Structure of Ferroelectric Pb1-xGexTe



Bruce D. Ravel, Eric J. Cockayne, K M. Rabe


The narrow band-gap semiconductor Pb_{1-x}Ge_xTe has a low-temperature ferroelectric rhombohedral phase whose average structure is a distorted rock salt structure. We have measured the Extended X-ray-Absorption Fine-Structure spectra of Pb_{1-x}Ge_xTe with x \approx 0.3 at the Ge and Te K edges and at the Pb L3 edge. By co-refining the spectra from these three edges, we have accurately determined the ground state structure of this material. We compare these results with recent first-principles density-functional calculations of total energies and find that these first-principles calculations of the ground state structure are in good agreement with the measured structure. Specifically we find a large lattice relaxation around the Ge site and a large displacement of the Ge atom from its nominal lattice position.
Journal of Synchrotron Radiation


EAFS, ground state structure, Pb<sub>1-x</sub>Ge<sub>x</sub>Te
Created May 1, 1999, Updated February 19, 2017