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C-H···O H-bonded complexes: how does basis set superposition error change their potential-energy surfaces?

Geometries, vibrational frequencies, and interaction energies of the CNH⋯O3 and HCCH⋯O3 complexes are calculated in a counterpoise-corrected (CP-corrected) potential-energy surface (PES) that corrects for the basis set superposition error (BSSE). Ab initio calculations are performed at the Hartree-Fock (HF) and second-order Møller-Plesset (MP2) levels, using the 6-31G(d,p) and D95++(d,p) basis sets. Interaction energies are presented including corrections for zero-point vibrational energy (ZPVE) and thermal correction to enthalpy at 298 K. The CP-corrected and conventional PES are compared; the unconnected PES obtained using the larger basis set including diffuse functions exhibits a double well shape, whereas use of the 6-31G(d,p) basis set leads to a flat single-well profile. The CP-corrected PES has always a multiple-well shape. In particular, it is shown that the CP-corrected PES using the smaller basis set is qualitatively analogous to that obtained with the larger basis sets, so the CP method becomes useful to correctly describe large systems, where the use of small basis sets may be necessary

© Journal of Chemical Physics, 2000, vol. 113, núm. 14, p. 5666-5674

American Institute of Physics

Author: Salvador Sedano, Pedro
Simon i Rabasseda, Sílvia
Duran i Portas, Miquel
Dannenberg, J. J.
Date: 2000
Abstract: Geometries, vibrational frequencies, and interaction energies of the CNH⋯O3 and HCCH⋯O3 complexes are calculated in a counterpoise-corrected (CP-corrected) potential-energy surface (PES) that corrects for the basis set superposition error (BSSE). Ab initio calculations are performed at the Hartree-Fock (HF) and second-order Møller-Plesset (MP2) levels, using the 6-31G(d,p) and D95++(d,p) basis sets. Interaction energies are presented including corrections for zero-point vibrational energy (ZPVE) and thermal correction to enthalpy at 298 K. The CP-corrected and conventional PES are compared; the unconnected PES obtained using the larger basis set including diffuse functions exhibits a double well shape, whereas use of the 6-31G(d,p) basis set leads to a flat single-well profile. The CP-corrected PES has always a multiple-well shape. In particular, it is shown that the CP-corrected PES using the smaller basis set is qualitatively analogous to that obtained with the larger basis sets, so the CP method becomes useful to correctly describe large systems, where the use of small basis sets may be necessary
Format: application/pdf
Citation: Salvador, P., Simon, S., Duran, M. i Dannenberg, J.J. (2000). C–H⋯O H-bonded complexes: how does basis set superposition error change their potential-energy surfaces?. Journal of Chemical Physics, 113 (14), 5666-5674. Recuperat 23 març 2011, a http://link.aip.org/link/doi/10.1063/1.1290010
ISSN: 0021-9606 (versió paper)
1089-7690 (versió electrònica)
Document access: http://hdl.handle.net/10256/3294
Language: eng
Publisher: American Institute of Physics
Collection: Reproducció digital del document publicat a: http://dx.doi.org/10.1063/1.1290010
Articles publicats (D-Q)
Is part of: © Journal of Chemical Physics, 2000, vol. 113, núm. 14, p. 5666-5674
Rights: Tots els drets reservats
Subject: Carboni
Energia de superfície
Enllaços químics
Estructura cristal·lina
Entalpia
Funcional de densitat, Teoria del
Hidrogen
Oxigen
Carbon
Chemical bonds
Density functionals
Enthalpy
Hydrogen
Layer structure (Solids)
Oxygen
Surface energy
Title: C-H···O H-bonded complexes: how does basis set superposition error change their potential-energy surfaces?
Type: info:eu-repo/semantics/article
Repository: DUGiDocs

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