2019-08-26T02:31:00Z
https://digital.csic.es/dspace-oai/request
oai:digital.csic.es:10261/14371
2016-02-16T04:58:43Z
com_10261_14181
com_10261_4
col_10261_14182
2009-07-06T08:31:11Z
urn:hdl:10261/14371
An inversion technique for the calculation of embedding potentials
Roncero, Octavio
Lara Castells, María Pilar de
Villarreal, Pablo
Flores, F.
Ortega, J.
Paniagua, Miguel
Aguado, Alfredo
Density functional theory
Electron correlations
HF calculations
Hydrogen neutral molecules
Localised states
Molecular electronic states
Potential energy surfaces
van der Waals forces
[PACS] Exchange-correlation functionals (in current density functional theory) (atoms and molecules)
[PACS] General molecular conformation and symmetry; stereochemistry
[PACS] Self-consistent-field methods in atomic and molecular physics
[PACS] Electron correlation calculations for diatomic molecules
[PACS] Potential energy surfaces for excited electronic states (atoms and molecules)
[PACS] Interatomic potentials and forces
12 pages, 9 figures.-- PACS nrs.: 31.15.eg; 33.15.Bh; 31.15.xr; 31.15.vn; 31.50.Df; 34.20.Cf.
A new embedding method to include local correlation in large systems is proposed. In this method the density of the whole system, calculated via density functional theory approaches, is partitioned in two pieces, one corresponding to the subsystem of interest and the rest to the environment. In the second step, an embedding potential is obtained iteratively using as a driving force the self-repulsion due to the density difference, in a similar form as proposed by Zhao et al. [Phys. Rev. A 50, 2138 (1994)], to obtain the “exact” exchange-correlation functional. Such potential is added to the Fock equation to build the localized molecular orbitals which are further used to include the local electronic correlation in the subsystem of interest. This method is an alternative to the previous DFT-based embedding methods first proposed by Wesolowski and Washell [J. Phys. Chem. 97, 8050 (1993)] and after enhanced by Govind et al. [J. Chem. Phys. 110, 7677 (1999)] and adapted to metal extended systems, which use density functionals to describe the kinetic energy contribution to the embedding potential, whose precise form has been largely treated in the literature and its crucial role is discussed here. The method is applied to hydrogen chains and its van der Waals interaction with H2. The results obtained are in very good agreement with exact calculations performed on the whole system, which demonstrates that the method proposed is a very promising route to introduce correlation in large systems.
2009-07-06T08:31:11Z
2009-07-06T08:31:11Z
2008-11-10
Artículo
Journal of Chemical Physics 129(18): 184104 (2008)
0021-9606
http://hdl.handle.net/10261/14371
10.1063/1.3007987
eng
http://dx.doi.org/10.1063/1.3007987
openAccess
American Institute of Physics