Correções vibracionais para as (hiper)polarizabilidades do sal de lítio de piridazina Li -H3C4N2

• Autor(a) principal: Silveira Júnior, Orlando José
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/4061
• topic: Lítio; Compostos orgânicos; Polarizabilidades; Lithium; Organic compounds; Polarizabilities; CIENCIAS EXATAS E DA TERRA::FISICA

In this work we report dynamic values for the (hyper)polarizabilities of lithium salt of pyridazine Li H3C4N2 including vibrational corrections. The electronic contributions were computed analytically at the single and double coupled cluster level (CCSD) through response theory, as implemented in the DALTON program, with the aug-cc-pVDZ basis set. The calculations for the vibrational corrections were carried out at the second-order Møller-Plesset level (MP2) by means of the perturbation theoretical method of Bishop and Kirtman and also using a variational approach proposed here. The results obtained for the zero-point vibrational average (zpva) corrections show that the two approaches lead practically to the same results, accounting for 2 and 6 % of the corresponding electronic contributions for polarizability and _rst hyperpolarizability, respectively. The results ob-tained show that, at the static limit, the pure vibrational corrections for the polarizability and _rst and second hyperpolarizabilities have the same order of magnitude of the corre-sponding electronic contributions. Comparisons between the results obtained through the two methods show that the perturbation theoretical method is not suitable to treat the system studied, whereas the variational methodology presented seems to be an alternative approach to treat anharmonic systems.