Comparison of basis set superposition error corrected perturbation theories for calculating intermolecular interaction energies
✍ Scribed by G. J. Halász; Á. Vibók; I. Mayer
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 281 KB
- Volume
- 20
- Category
- Article
- ISSN
- 0192-8651
No coin nor oath required. For personal study only.
✦ Synopsis
Recently, two different but conceptually similar basis set Ž . superposition error BSSE free second-order perturbation theoretical schemes were developed by us that are being based on the chemical Hamiltonian Ž . approach CHA . Using these CHA-MP2 and CHA-PT2 methods, a comparison is made between the a posteriori and a priori BSSE correction schemes at the correlated level. Sample calculations are presented for four hydrogen bonded . . . . . . . . Ž . complexes HF H N , HF H O , H S HF , and H O HCl in nine 3 2 2 2
Ž . different basis sets from 6᎐31G to TZV**qq . The results show that the BSSE content is very significant in the interaction energy if electron correlation is accounted for, so removing the BSSE is very important. The differences of the two perturbational theories discussed are connected solely with the different one electron orbital sets used for building up the unperturbed single determinant wave function.