Ab initio benchmark study for the oxidative addition of CH4 to Pd: importance of basis-set flexibility and polarization
dc.contributor.author
dc.date.accessioned
2011-03-28T13:29:39Z
dc.date.available
2010-12-14T12:55:53Z
2011-03-28T13:29:39Z
dc.date.issued
2004
dc.identifier.citation
Theodoor De Jong, G., Solà, M., Visscher, L., i Bickelhaupt, F.M. (2004). Ab initio benchmark study for the oxidative addition of CH4 to Pd: importance of basis-set flexibility and polarization. Journal of Chemical Physics, 121 (20), 9982-9992. Recuperat 28 març 2011,a http://link.aip.org/link/doi/10.1063/1.1792151
dc.identifier.issn
0021-9606
dc.identifier.uri
dc.description.abstract
To obtain a state-of-the-art benchmark potential energy surface (PES) for the archetypal oxidative addition of the methane C-H bond to the palladium atom, we have explored this PES using a hierarchical series of ab initio methods (Hartree-Fock, second-order Møller-Plesset perturbation theory, fourth-order Møller-Plesset perturbation theory with single, double and quadruple excitations, coupled cluster theory with single and double excitations (CCSD), and with triple excitations treated perturbatively [CCSD(T)]) and hybrid density functional theory using the B3LYP functional, in combination with a hierarchical series of ten Gaussian-type basis sets, up to g polarization. Relativistic effects are taken into account either through a relativistic effective core potential for palladium or through a full four-component all-electron approach. Counterpoise corrected relative energies of stationary points are converged to within 0.1-0.2 kcal/mol as a function of the basis-set size. Our best estimate of kinetic and thermodynamic parameters is -8.1 (-8.3) kcal/mol for the formation of the reactant complex, 5.8 (3.1) kcal/mol for the activation energy relative to the separate reactants, and 0.8 (-1.2) kcal/mol for the reaction energy (zero-point vibrational energy-corrected values in parentheses). This agrees well with available experimental data. Our work highlights the importance of sufficient higher angular momentum polarization functions, f and g, for correctly describing metal-d-electron correlation and, thus, for obtaining reliable relative energies. We show that standard basis sets, such as LANL2DZ+ 1f for palladium, are not sufficiently polarized for this purpose and lead to erroneous CCSD(T) results. B3LYP is associated with smaller basis set superposition errors and shows faster convergence with basis-set size but yields relative energies (in particular, a reaction barrier) that are ca. 3.5 kcal/mol higher than the corresponding CCSD(T) values
dc.format.mimetype
application/pdf
dc.language.iso
eng
dc.publisher
American Institute of Physics
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Reproducció digital del document publicat a: http://dx.doi.org/10.1063/1.1792151
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© Journal of Chemical Physics, 2004, vol. 121, núm. 20, p. 9982-9992
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dc.title
Ab initio benchmark study for the oxidative addition of CH4 to Pd: importance of basis-set flexibility and polarization
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info:eu-repo/semantics/article
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info:eu-repo/semantics/openAccess
dc.identifier.doi
dc.identifier.eissn
1089-7690