Theoretical study of transition metal monocarbides: MnC and CoC. / Estudo teórico de monocarbetos de metais de transição: MnC e CoC

AUTOR(ES)

João Paulo Gobbo

DATA DE PUBLICAÇÃO

2006

RESUMO

In this work, high level ab initio multiconfigurational methods were employed to study the electronic structures and chemical bondings of several electronic states of two 3d transition metal monocarbides: MnC and CoC. The lowest-lying quartet, sextet, and octuplet electronic states of MnC, correlating with the three lowest-lying atomic dissociation channels, were investigated theoretically for the first time, with state-of-the-art Multireference Configuration Interaction (MRCI) approach, based on Complete-Active-Space Self-Consistent-Field (CASSCF) wave functions and extensive basis sets. Excitation energies, equilibrium internuclear distances, dissociation energies, and spectroscopic constants for all 36 electronic states will be reported. Franck-Condon factos, Einstein coefficients, and radiative lifetimes for the X-A electronic transition will also be presented. As to the colbalt monocarbide (CoC), the CASSCF and Second Order Perturbation Theory (CASPT2) methods were employed to study its low-lying electronic dublet states. Three new states were identified. The results support the previous assignment fo the 13000 – 14500 cm-1, but unlike previous suggestions, another electronic configuration were found as the most important for the description of this state.

ASSUNTO(S)

métodos ab initio multiconfiguracionais multireference ab initio methods metais de transição transition metals

Documentos Relacionados

• Estudo teórico de diatômicas homo e heteronucleares de metais de transição
• Estudo ab-initio de propriedades estruturais e magnéticas de nanopartículas de metais de transição
• Paligorsquita como adsorvente para íons de metais de transição: Estudos cinéticos e do equilíbrio
• Nanocompósitos de blendas poliméricas condutoras e óxidos de metais de transição
• Estudo teórico de propriedades químicas de sistemas hetero-macrocíclos que complexam metais de transição divalentes da primeira e segunda filas