On Wednesday, March 1, 2017 11:54:01 AM CET Azadi, Sam wrote: > Dear Experts, > > I’m interested to know that how the amplitude of atomic displacements are > defined in DFPT calculations?
Hello, in density function perturbation theory, contrary to finite-differenes method, there is no atom displacement: quantum-mechanics perturbation theory is used. See this reference: <http://journals.aps.org/rmp/abstract/10.1103/RevModPhys. 73.515> for details on the method how it is implemented in QE. Tis lecture from Stefano Baroni to get a quick idea: < https:// www.dropbox.com/s/xi06fv6oz07j9du/EUSPec%202016%20%281%29.pdf?dl=0> -- Dr. Lorenzo Paulatto IdR @ IMPMC -- CNRS & Université Paris 6 phone: +33 (0)1 442 79822 / skype: paulatz www: http://www-int.impmc.upmc.fr/~paulatto/ mail: 23-24/423 Boîte courrier 115, 4 place Jussieu 75252 Paris Cédex 05 _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
