First-principles quantum mechanical characterization of structure and NLO properties of Li+@C 60

Abstract

We present here our first-principles density functional theory (DFT) calculations of the potential energy and dipole moment function for Li+C60. We also present the results for the equilibrium geometry, dipole moment and polarizability dispersion obtained from ab initio Hartree-Fock (HF) calculations. The calculated equilibrium position of Li inside the C60 cage agrees with other theoretical calculations. The dipole moments calculated by the DFT and HF calculations, while differing from each other by almost a factor of two, are considerably smaller than a recent DFT result. The polarizability tensor calculated at lambda equals infinity (static) and at lambda equals 1064 nm are very nearly isotropic, indicating little deformation of the spherically symmetric charge distribution of C60. Quantitatively, the alpha values of the Li+C60 complex are very close to the corresponding value for the C60 molecule.