Issue |
Europhys. Lett.
Volume 43, Number 2, July II 1998
|
|
---|---|---|
Page(s) | 183 - 188 | |
Section | Condensed matter: structure, thermal and mechanical properties | |
DOI | https://doi.org/10.1209/epl/i1998-00338-1 | |
Published online | 01 September 2002 |
Determination of the elastic tensor in low-symmetry structures
1
Institute for Materials Research,
Tohoku University, Aoba-ku - 980-77 Sendai, Japan
2
Department of Physics, Brookhaven National Laboratory Upton, NY
11973-5000, USA
Received:
13
February
1998
Accepted:
4
June
1998
A method for determining the elastic constants of low-symmetry crystal
structures with internal coordinates through the computation of the
Hellmann-Feynman forces is described.
The approach applies to cases where previous methods were impractical, namely
cases where the macroscopic strains are coupled to the internal degrees of
freedom.
The approach is illustrated for triclinic , which has 12 internal
degrees of freedom.
In non-cubic structures invariances must be imposed on the force constants,
regardless of whether those interatomic force constants were obtained
from a supercell- or from a linear-response approach.
Moreover, it is shown that important aspects of crystal bonding are easily
analyzed in terms of the force constants.
PACS: 62.20.-x – Mechanical properties of solids / 62.20.Dc – Elasticity, elastic constants / 63.20.-e – Phonons in crystal lattices
© EDP Sciences, 1998
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.