Self-Trapping of Single and Paired Electrons in Ge₂Se₃

Authors

A. H. Edwards, Air Force Research Laboratory, AFRL/RVSE
Kristy A. Campbell, Boise State UniversityFollow
Andrew C. Pineda, University of New Mexico

Document Type

Article

Publication Date

5-16-2012

DOI

http://dx.doi.org/10.1088/0953-8984/24/19/195801

Abstract

We report the theoretical prediction of single and paired electron self-trapping in Ge₂Se₃. In finite atomic cluster, density functional calculations, we show that excess single electrons in Ge₂Se₃ are strongly localized around single germanium dimers. We also find that two electrons prefer to trap around the same germanium dimer, rupturing a neighboring Ge–Se bond. Localization is less robust in periodic, density functional calculations. While paired electron self-trapping is present, as shown by wavefunction localization around a distorted Ge–Ge dimer, single-electron trapping is not. This discrepancy appears to depend only on the boundary conditions and not on the exchange–correlation potential or basis set. For single- and paired-electron trapping, we report the adiabatic barriers to motion and we estimate hopping rates and freeze-in temperatures. For the single trapped electron, we also predict the ⁷³Ge and ⁷⁷Se hyperfine coupling constants.

Publication Information

Edwards, A. H.; Campbell, Kristy A.; and Pineda, Andrew C.. (2012). "Self-Trapping of Single and Paired Electrons in Ge₂Se₃". Journal of Physics: Condensed Matter, 24(19), 1-9.