Open AccessIn Situ Pseudopotentials for Electronic Structure Theory
Author(s) -
Kristofer Björnson,
J. M. Wills,
M. Alouani,
Oscar Grånäs,
Patrik Thunström,
Chin Shen Ong,
Olle Eriksson
Publication year - 2021
Publication title -
journal of physical chemistry. c./journal of physical chemistry. c
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.401
H-Index - 289
eISSN - 1932-7455
pISSN - 1932-7447
DOI - 10.1021/acs.jpcc.1c04791
Subject(s) - pseudopotential , density functional theory , electron , wave function , quantum mechanics , eigenvalues and eigenvectors , electronic structure , condensed matter physics , electronic band structure , physics , function (biology) , chemistry , atomic physics , biology , evolutionary biology
We present a general method of constructing in situ pseodopotentials from first-principles, all-electron, and full-potential electronic structure calculations of a solid. The method is applied to bcc Na, at low-temperature equilibrium volume. The essential steps of the method involve (i) calculating an all-electron Kohn-Sham eigenstate, (ii) replacing the oscillating part of the wave function (inside the muffin-tin spheres) of this state, with a smooth function, (iii) representing the smooth wave function in a Fourier series, and (iv) inverting the Kohn-Sham equation, to extract the pseudopotential that produces the state generated in steps i-iii. It is shown that an in situ pseudopotential can reproduce an all-electron full-potential eigenvalue up to the sixth significant digit. A comparison of the all-electron theory, in situ pseudopotential theory, and the standard nonlocal pseudopotential theory demonstrates good agreement, e.g., in the energy dispersion of the 3s band state of bcc Na.