Construction of integrable model Kohn-Sham potentials by analysis of the structure of functional derivatives
- Department of Chemistry, University of Western Ontario, London, Ontario N6A 5B7 (Canada)
A directly approximated exchange-correlation potential should, by construction, be a functional derivative of some density functional in order to avoid unphysical results. Using generalized gradient approximations (GGAs) as an example, we show that functional derivatives of explicit density functionals have a very rigid inner structure, the knowledge of which allows one to build the entire functional derivative from a small part. Based on this analysis, we develop a method for direct construction of integrable Kohn-Sham potentials. As an illustration, we transform the model potential of van Leeuwen and Baerends (which is not a functional derivative) into a semilocal exchange potential that has a parent GGA, yields accurate energies, and is free from the artifacts inherent in existing semilocal potential approximations.
- OSTI ID:
- 21529069
- Journal Information:
- Physical Review. A, Vol. 83, Issue 1; Other Information: DOI: 10.1103/PhysRevA.83.012509; (c) 2011 American Institute of Physics; ISSN 1050-2947
- Country of Publication:
- United States
- Language:
- English
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