title: Theoretical study of CH4-CH4, CHF3-CH4, CH4-H2O, and CHF3-H2O dimers.
abstract: We have studied systems with typical hydrogen bonding and others with interaction involving hydrogen. CH(4)-CH(4), CH(4)-H(2)O, CHF(3)-CH(4), and CHF(3)-H(2)O dimers were studied using MPWB1K, PBE1PBE, MP2, and QCISD levels of theory with a large number of basis functions. The Pople 6-31+G(2d), 6-311++G(2d,2p), and 6-311++G(3df,3pd) as well as Dunning augmented aug-cc-pVDZ and aug-cc-pVTZ basis sets were used. The dimer geometries were fully optimized. An optimal basis set was determined for these systems to achieve a suitable compromise between accuracy and computational feasibility. A proper strategy was found for the electronic property calculations of dimers studied: the use of aug-cc-pVDZ as the optimal basis set at MP2 level. Dipole moments, polarizabilities, BSSE effects, and DeltaZPE were also analyzed for these dimers.
authors: Instituto de Química, Laboratório de Química Computacional, Universidade de Brasília, CP 4478, Brasília, DF, 70904-970, Brazil. lopes@unb.br
authors: João B L
authors: JB
authors: Martins
authors: José R S
authors: JR
authors: Politi
authors: Edgardo
authors: E
authors: Garcia
authors: Alessandra F A
authors: AF
authors: Vilela
authors: Ricardo
authors: R
authors: Gargano
mesh_terms: D005617:Chlorofluorocarbons, Methane / Q000737:chemistry*; D019281:Dimerization; D008697:Methane / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D011789:Quantum Theory; D013816:Thermodynamics; D014867:Water / Q000737:chemistry*
chemical_list: D005617:Chlorofluorocarbons, Methane; D014867:Water; D008697:Methane; C009554:fluoroform