Communication: A novel implementation to compute MP2 correlation energies without basis set superposition errors and complete basis set extrapolation

Extrapolation of electron correlation energies to finite and complete basis set targets.

The electron correlation energy of two-electron atoms is known to converge asymptotically as approximately (L+1)(-3) to the complete basis set limit, where L is the maximum angular momentum quantum number included in the basis set. Numerical evidence has established a similar asymptotic convergence approximately X(-3) with the cardinal number X of correlation-consistent basis sets cc-pVXZ for c...

Extrapolation to the Complete Basis Set Limit for Binding Energies of Noncovalent Interactions

A means of extrapolating from double and triple-valence basis sets to a complete basis set is examined in the context of the pnicogen bonds in the BH2P···NH3 complexes, with B = CH3, H, NH2, CF3, OH, Cl, F, and NO2. Binding energies converge smoothly, and the trends for the various substituents B are unaffected by the basis set size, extrapolation, or level of inclusion of electron correlation,...

Møller-Plesset perturbation energies and distances for HeC20 extrapolated to the complete basis set limit

The potential energy surface for the C(20)-He interaction is extrapolated for three representative cuts to the complete basis set limit using second-order Møller-Plesset perturbation calculations with correlation consistent basis sets up to the doubly augmented variety. The results both with and without counterpoise correction show consistency with each other, supporting that extrapolation with...

Primary and secondary basis set superposition error at the SCF and MP2 levels. H3N‐‐Li+ and H2O‐‐Li+

Second-order Møller-Plesset perturbation theory without basis set superposition error. II. Open-shell systems.

The basis set superposition error-free second-order Møller-Plesset perturbation theory of intermolecular interactions, based on the "chemical Hamiltonian approach," which has been introduced in Part I, is applied here to open-shell systems by using a new, effective computer realization. The results of the numerical examples considered (CH(4) em leader HO, NO em leader HF) showed again the perfe...