Higher-order interaction energies for a system of N arbitrary molecules in the light of spherical tensor theory

摘要: The Rayleigh–Schrodinger perturbation treatment accompanied by a multipole expansion of the interaction potential can be used in quantum‐mechanical studies long‐range intermolecular forces. total third‐order energy system N molecules separates into several induction and dispersion categories. Only some them are purely pairwise additive. In present paper closed expressions for all possible categories anisotropic collection arbitrary derived, which orientational dependence is pushed to its limits. derivation based on spherical tensor formalism. formulas energies directly related moments irreducible (hyper)polarizabilities interacting body‐fixed frames. same achieved after employing simple approximations. treated as an extension t...