High orders corrections to the Van der Waals–London forces. II. Interaction of two molecules with isotropic polarizabilities

✍ Scribed by J. P. Malrieu

• Publisher: John Wiley and Sons
• Year: 1971
• Tongue: English
• Weight: 542 KB
• Volume: 5
• Category: Article
• ISSN: 0020-7608
• DOI: 10.1002/qua.560050408

✦ Synopsis

Abstract

The infinite summation of intermolecular ring diagrams is extended to any pair of interacting molecules with isotropic polarizabilities. The calculation no longer requires the use of a minimal basis set. The polarizabilities α,α′ may be factorized at all orders, and an expression is derived, which gives modified Van der Waals energies. For heavy atoms the series converges if αα′/R^6^ is smaller than 1, R being the interatomic distance. This inequality is easily satisfied for the Van der Waals distances, and in practice the correction due to the high orders of the perturbation expansion remains weak. The role of the EPV diagrams and the connection with a configuration interaction treatment are discussed.