O efeito da correlação eletrônica em clusters de Boro aromáticos: um estudo via Monte Carlo quântico

• Autor(a) principal: Moreira, Emanuel Melo Isaac
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/001300000ckb8
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/5096
• topic: Aromaticidade; Correlação eletrônica; Monte Carlo Quântico; Aromaticity; Electronic correlation; Quantum Monte Carlo; FISICA::FISICA DA MATERIA CONDENSADA

In this work we used a combination of density functional theory and quantum Monte Carlo methods to study the effect of electron correlation on stability and aromaticity of anionic Boron clusters (B− 3 and B− 4 ). We found that, in general, the cyclic isomer is energetically more stable than its open linear counterpart. Based on principles of minimum energy and electrophilicity, and maximum hardness, diffusion Monte Carlo indicates that B− 3 cluster is aromatic, however, the results are not conclusive with respect to the B− 4 cluster. Calculations were also performed within the Hartree–Fock approximation. From the obtained results, we analysed the impact of the electron correlation effects in these clusters and found that the correlation of the electrons contributes significantly to the ionization potential and electron affinities varying between 31% and 66% of their total values.