| Issue |
J. Phys. III France
Volume 7, Number 12, December 1997
|
|
|---|---|---|
| Page(s) | 2281 - 2292 | |
| DOI | https://doi.org/10.1051/jp3:1997259 | |
J. Phys. III France 7 (1997) 2281-2292
Dislocation and Grain Boundary Energies in Si and Ge from an Anharmonic Bond Charge Model
H. Teichler and J. WilderInstitut f$\ddot{\rm u}$r Metallphysik, Universit$\ddot{\rm a}$t G$\ddot{\rm o}$ttingen, 37073 G$\ddot{\rm o}$ttingen, Germany
(Received 3 October 1996, revised 16 September 1997, accepted 16 Septembre 1997)
Abstract
The paper presents calculated line energy values for the reconstructed 60
and 90
glide-set partial dislocations in Si and Ge, formation and migration energy for the reconstructed kink on the reconstructed
90
partials, and energy data for the symmetric
and for two variants of the symmetric
tilt grain boundaries. Criteria are formulated to identify interatomic force field models which are able to provide reliable
energy estimates. The anharmonic bond charge (a.bc) model is introduced as an example that approximately fulfills the basic
criteria, i.e., describes well the second and third order elastic constants and the phonon dispersion curves. Deviations between energy
estimates from the a.bc model and less reliable approaches are discussed. It is shown that in case of the
tilt grain boundary the a.bc model gives different energetical ranking for the so-called
A and the
B variants in Si and Ge, in agreement with the experimental observations.
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