Electron Localization Function at the Correlated Level: A Natural Orbital Formulation

In this work we present a 2-fold approximation for the calculation of the electron localization function (ELF) which avoids the use of the two-particle density (2-PD). The first approximation is used for the calculation of the ELF itself and the second one is used to approximate pair populations int...

Descripción completa

Detalles Bibliográficos
Autores: Feixas Geronès, Ferran, Matito i Gras, Eduard, Duran i Portas, Miquel, Solà i Puig, Miquel, Silvi, Bernard
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2010
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:10256/12201
Acceso en línea:http://hdl.handle.net/10256/12201
Access Level:acceso embargado
Palabra clave:Orbitals moleculars
Molecular orbitals
Química quàntica
Quantum chemistry
Electrons -- Distribució
Electron distribution
Descripción
Sumario:In this work we present a 2-fold approximation for the calculation of the electron localization function (ELF) which avoids the use of the two-particle density (2-PD). The first approximation is used for the calculation of the ELF itself and the second one is used to approximate pair populations integrated in the ELF basins. Both approximations only need the natural orbitals and their occupancies, which are available for most methods used in electronic structure calculations. In this way, methods such as CCSD and MP2 can be used for the calculation of the ELF despite the lack of a pertinent definition of the 2-PD. By avoiding the calculation of the 2-PD, the present formulation provides the means for routine calculations of the ELF in medium-size molecules with correlated methods. The performance of this approximation is shown in a number of examples