Polarizabilities and hyperpolarizabilities of F2

Abstract

The dipole (α), quadrupole (C), and dipole–octopole (E) polarizabilities, the dipole–dipole–quadrupole (B) and second dipole (γ) hyperpolarizabilities, and the quadrupole (Θ) and hexadecapole (Φ) moments are calculated for the ground state of F₂ at its equilibrium bond length. These properties are obtained from fourth‐order Mo/ller–Plesset perturbation theory energies of F₂ in the presence of various configurations of point charges; the perturbation theory uses the self‐consistent‐field wave function for F₂ perturbed by charges as the zeroth‐order wave function. Our best vibrationless estimates for the isotropic averages are ᾱ=8.485 e² a²₀ E⁻¹_h, C̄=23.588 e² a⁴₀ E⁻¹_h, B̄=−84 e³ a⁴₀ E⁻²_h, and γ̄=512 e⁴ a⁴₀ E⁻³_h. The ᾱ value is in good agreement with experiment, whereas our vibrationally corrected estimate of Θ_zz ≂0.74 e a²₀ should be more accurate than the existing experimental estimates.