Hirschfelder-Silbey perturbation expansion

Chalasinski G, Jeziorski B, Szalewicz K (1977) On the convergence properties of the Rayleigh-Schrodinger and the Hirschfelder-Silbey perturbation expansions for molecular interaction energies. Int J Quantum Chem 11 247-257... 

Table 3 Convergence of the symmetrized Rayleigh-Schrodinger and Hirschfelder-Silbey perturbation expansions for the interaction of two ground-state helium atoms at various interatomic distances. The B71 basis set was used. E(n) and S(n) are defined as in Table 1. Energies are in //hartree.

All the SAPT methods considered so far have used a single operator projecting onto a specific subspace c a b- The HS perturbation theory, introduced by Hirschfelder and Silbey [50], follows a different, multistate philosophy. It performs a perturbation expansion for a primitive func-... 

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