All-electron formalism for total energy strain derivatives and stress tensor components for numeric atom-centered orbitals

作者：Knuth Franz; Carbogno Christian^*; Atalla Viktor; Blum Volker; Scheffler Matthias

来源：Computer Physics Communications, 2015, 190: 33-50.

DOI：10.1016/j.cpc.2015.01.003

• Stress tensor
• Strain derivatives
• Density-functional theory
• Hybrid functionals
• Atom-centered basis functions

We derive and implement the strain derivatives of the total energy of solids, i.e., the analytic stress tensor components, in an all-electron, numeric atom-centered orbital based density-functional formalism. We account for contributions that arise in the semi-local approximation (LDA/GGA) as well as in the generalized Kohn-Sham case, in which a fraction of exact exchange (hybrid functionals) is included. In this work, we discuss the details of the implementation including the numerical corrections for sparse integrations grids which allow to produce accurate results. We validate the implementation for a variety of test cases by comparing to strain derivatives performed via finite differences. Additionally, we include the detailed definition of the overlapping atom-centered integration formalism used in this work to obtain total energies and their derivatives.

• 出版日期2015-5