Full-CI calculation of imaginary frequency-dependent dipole polarizabilities of ground state LiH and the C6 dispersion coefficients of LiH–LiH

Full-CI calculations of frequency-dependent dipole polarizabilities of ground state LiH have been performed in the imaginary frequency range 0–20 a.u. using an extended set of 109 Gaussian type orbitals (GTOs). A 32-points Gauss–Legendre quadrature of the Casimir–Polder formula over imaginary frequencies allows calculation of the dipole dispersion constants for the LiH–LiH homodimer, from which isotropic C6 and anisotropy γ6 dispersion coefficients are derived for the first time.