Complex polarization propagator method for calculation of dispersion coefficients of extended pi-conjugated systems:The C_6 coefficients of polyacenes and C_(60)

摘要

The frequency-dependent polarizabilities and the C_6 dipole-dipole dispersion coefficients for the first members of the polyacenes namely benzene,naphthalene,anthracene,and naphthacene as well as the fullerene C_(60) have been calculated at the time-dependent Hartree-Fock level and the time-dependent density-functional theory level with the hybrid B3LYP exchange-correlation functional.The dynamic polarizabilities at imaginary frequencies are obtained with use of the complex linear polarization propagator method and the C_6 coefficients are subsequently determined from the Casimir-Polder relation.We report the first ab initio calculations of the C_6 coefficients for the molecules under consideration,and our recommended value for the dispersion coefficient of the fullerene is 101.0 a.u.