Empirical corrections in the G3X and G3X(CCSD) theories combined with a compact effective pseudopotential

Autor(es)

Silva, Cleuton de Souza ^{[1, 2]} ; Custodio, Rogerio ^[2]

Afiliação do(s) autor(es)

^[1] Univ Fed Amazonas, Inst Ciencias Exatas & Tecnol, Campus Itacoatiara, BR-69100021 Itacoatiara, Amazonas - Brazil

^[2] Univ Estadual Campinas, Inst Quim, POB 6154, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: THEORETICAL CHEMISTRY ACCOUNTS; v. 137, n. 2 JAN 25 2018.
• Citações Web of Science: 3

Resumo

The G3X-CEP and G3X(CCSD)-CEP composite methods were developed by combining a compact effective pseudopotential (CEP) with the G3X and G3X(CCSD) all-electron methods. The G3/05 test set was used as reference data to analyze the performance of these methods by calculating enthalpies of formation, ionization energies, electron affinities, proton affinities, and molecular atomization energies. Tests were carried out considering different numbers of higher-level correction (HLC) parameters as well as a scaling of the experimental atomization energies of the elements used to determine the enthalpies of formation. The overall behavior of G3X-CEP and G3X(CCSD)-CEP calculations considering six HLC parameters presented a mean absolute error around 1.15 kcal mol(-1) for all calculated properties. This tendency is intermediate to the G3CEP and G4CEP methods. The use of scaled experimental atomization energies of the elements provided a mean absolute error around 1.11 kcal mol(-1), which is similar to the one obtained by the G4CEP theory (1.09 kcal mol(-1)). The G3X-CEP and G3X(CCSD)-CEP enthalpies of formation were significantly improved with respect to experimental results. Molecular atomization energies showed a modest improvement, while the ionization energies and electronic affinities were slightly affected indirectly by the reoptimized HLC parameters. The proton affinities were nearly unaffected. (AU)

• Processo FAPESP: 13/08293-7 - CECC - Centro de Engenharia e Ciências Computacionais
• Beneficiário: Munir Salomao Skaf
• Linha de fomento: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs
• Processo FAPESP: 17/11485-6 - Desenvolvimentos computacionais e teóricos baseados em métodos ab initio e na Teoria do Funcional de Densidade
• Beneficiário: Rogério Custodio
• Linha de fomento: Auxílio à Pesquisa - Regular