Lithium dipole properties and van der Waals constants using a pseudo spectral one-centre method

A pseudo spectral one-centre method is used to evaluate the moments of the dipole oscillator strength distribution for the ground-state Li atom and the van der Waals constants for the ground-state Li-Li, Li-He and Li-H interactions. Various combinations of C.I. type Li atom ground and excited 2 P 0-state wavefunctions are used to construct the required pseudo spectral dipole oscillator strengths and excitation energies. The analysis of all the pseudo-state data yields recommended values for the Li dipole properties and van der Waals constants that are probably more accurate than those obtained previously. The calculations illustrate some of the advantages of the pseudo spectral approach for the evaluation of atomic and molecular properties and interaction energies.