On the validity of Pople's infinite-order Møller-Plesset extrapolation and an alternative formula within MBP/CC theories
✍ Scribed by J.M.L. Martin; J.P. François; R. Gijbels
- Publisher
- Elsevier Science
- Year
- 1989
- Tongue
- English
- Weight
- 566 KB
- Volume
- 157
- Category
- Article
- ISSN
- 0009-2614
No coin nor oath required. For personal study only.
✦ Synopsis
For the first-row open-and closed-shell hydrides and the 6-311 +G(d, p)B and 6-311 +G(Zdf, p)B basis sets, the validity of Pople's higher-order Mgller-Plesset correction is investigated by comparison with augmented coupled cluster energies. A new correction formula is suggested which involves no additional computation time. Dissociation energies based on Pople's correction are overestimated systematically when triple excitations are involved. With the new formula, excellent agreement with CC energies is obtained, except in cases of slow MP series convergence. The augmented CC calculations in the 6-311+ G(Zdf, p)B basis set yield dissociation energies which are extremely close to the experimental values.