Premium
Nuclear‐relaxed elastic and piezoelectric constants of materials: Computational aspects of two quantum‐mechanical approaches
Author(s) -
Erba Alessandro,
Caglioti Dominique,
ZicovichWilson Claudio Marcelo,
Dovesi Roberto
Publication year - 2017
Publication title -
journal of computational chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.907
H-Index - 188
eISSN - 1096-987X
pISSN - 0192-8651
DOI - 10.1002/jcc.24687
Subject(s) - piezoelectricity , quantum , force constant , relaxation (psychology) , statistical physics , displacement (psychology) , constant (computer programming) , interatomic potential , matrix (chemical analysis) , classical mechanics , physics , computer science , materials science , molecular dynamics , quantum mechanics , molecule , psychology , social psychology , acoustics , composite material , psychotherapist , programming language
Two alternative approaches for the quantum‐mechanical calculation of the nuclear‐relaxation term of elastic and piezoelectric tensors of crystalline materials are illustrated and their computational aspects discussed: (i) a numerical approach based on the geometry optimization of atomic positions at strained lattice configurations and (ii) a quasi‐analytical approach based on the evaluation of the force‐ and displacement‐response internal‐strain tensors as combined with the interatomic force‐constant matrix. The two schemes are compared both as regards their computational accuracy and performance. The latter approach, not being affected by the many numerical parameters and procedures of a typical quasi‐Newton geometry optimizer, constitutes a more reliable and robust mean to the evaluation of such properties, at a reduced computational cost for most crystalline systems. © 2016 Wiley Periodicals, Inc.