> How can we exert a shear force? A short list of readings Introduction to Solid State Physics, C. Kittel, Theory of Elasticity, Landau &Lifshits
For simulation with Quantum ESPRESSO, you define a strain and the code calculates stress. You must obtain a relaxed structure (calculation='vc-relax'), then you apply deformations to the lattice vectors, but relaxing the atom positions (calculation='relax') One simple example of how to deform the lattice vectors is explained in J. Appl. Phys. 99, 103504 (2006). See also Phys Rev B 1995; 51: 17431. An explanation on the theory of ab initio stress calculations is in Nielsen OH, Richard M. First?Principles Calculation of Stress. Phys Rev Lett 1983;50: 697, and more detailed in PRB 32, 3780 (1985) Good luck -- Eduardo Menendez Departamento de Fisica Facultad de Ciencias Universidad de Chile Phone: (56)(2)9787439 URL: http://fisica.ciencias.uchile.cl/~emenendez Let's pray for the 33 trapped miners! Four months to rescue. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20100929/e2c674c7/attachment.htm