Estrutura eletrônica em sistemas moleculares de interesse espacial e atmosférico.

In this work, electronic structure calculations of high theoretical level were made through multiconfigurational methods aiming at three objectives: the first, to propose a new extrapolation method of the dynamic correlation energies to the Complete Basis Set (CBS) - limit, where a good agreement wi...

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Detalles Bibliográficos
Autor: Coura, Daniel Vitor Barbosa
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2023
País:Brasil
Institución:Universidade Federal do Espírito Santo (UFES)
Repositorio:Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
Idioma:portugués
OAI Identifier:oai:repositorio.ufes.br:10/12317
Acceso en línea:http://repositorio.ufes.br/handle/10/12317
Access Level:acceso abierto
Palabra clave:Interação molecular
Cálculos ab initio
Superfície de energia potencial
Extrapolação
Correlação dinâmica
HN2
HCO
Física
Descripción
Sumario:In this work, electronic structure calculations of high theoretical level were made through multiconfigurational methods aiming at three objectives: the first, to propose a new extrapolation method of the dynamic correlation energies to the Complete Basis Set (CBS) - limit, where a good agreement with results available in the bibliography is obtained, even when the (d, t) pair of hierarchical numbers is used to perform the extrapolation; the second objective is to fit ab initio extrapolated points to the CBS limit via the unified singlet- and triplet-pair method of the molecular system HN2 to an analytic function using the double many-body expansion method for the quartet state, being the first potential energy surface constructed for this state, allowing, for the first time, the prediction of the role played by the quartet state in N(4S) + NHN(4S) + NH(˜X³Σ¯) collisions; and the third, to build a potential energy surface using the extrapolation method developed here for the molecular system HCO, this work is in progress and a preliminary fit is shown.