SDTQ-MPPT(4) electric moments and static polarizabilities for Li₂(X¹Σ⁺_g)

Abstract

Fourth order Møller-Plesset Perturbation Theory, MPPT(4), was applied to the calculation of the quadrupole moment Θ, the dipole polarizability α, the second dipole hyperpolarizability γ and the dipole-dipole-quadrupole hyperpolarizability B of Li₂(X ¹Σ⁺ _g ). In addition, LCAO-SCF values are reported for the hexadecapole moment Φ, the quadrupole-quadrupole hyperpolarizability C and the dipole-octopole hyperpolarizability E. The present study includes the dependence of the calculated values on the basis set for all properties. The correlated values of γ and B appear for the first time in the literature. The MPPT(4) values of Θ and the isotropic components of α, γ and B, calculated with a (12s9p1d1f)[6s6p1d1f] basis set, are 10·443 ea ² ₀, 211 e ² a ² ₀ E ^-1 _h , 823 × 10³ e ⁴ a ⁴ ₀ E ^-3 _h and -714 × 10² e ³ a ⁴ ₀ E ^-2 _h respectively at the experimental internuclear separation of 5·051 a ₀.