Chemistry, Ames Laboratory
Journal or Book Title
Journal of Chemical Physics
The recently introduced method of correlationenergy extrapolation by intrinsic scaling (CEEIS) is used to calculate the nonrelativistic electron correlations in the valence shell of the F2 molecule at 13 internuclear distances along the ground state potential energy curve from 1.14Åto8Å, the equilibrium distance being 1.412Å. Using Dunning’s correlation-consistent double-, triple-, and quadruple-zeta basis sets, the full configuration interaction energies are determined, with an accuracy of about 0.3mhartree, by successively generating up to octuple excitations with respect to multiconfigurational reference functions that strongly change along the reaction path. The energies of the reference functions and those of the correlationenergies with respect to these reference functions are then extrapolated to their complete basis set limits. The applicability of the CEEIS method to strongly multiconfigurational reference functions is documented in detail.
Copyright 2007 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.
American Institute of Physics
Bytautas, Laimutis; Nagata, Takeshi; Gordon, Mark S.; and Ruedenberg, Klaus, "Accurate Ab Initio Potential Energy Curve of F2. I. Nonrelativistic Full Valence Configuration Interaction Energies Using the Correlation Energy Extrapolation by Intrinsic Scaling Method" (2007). Chemistry Publications. 486.