Molecular polarizability in quantum defect theory: Nonpolar molecules

The method of reduced-added Green's function in quantum defect approximation [V. E. Chernov, D. L. Dorofeev, I. Yu. Kretinin, and B. A. Zon, Phys. Rev. A 71, 022505 (2005)] is generalized for calculation of dynamic polarizabilities of nonpolar molecules. The method is applied to alkali-metal dimers Li-2, Na-2, and Rb-2. The accuracy achieved in benchmark calculation (H-2 molecule) is comparable to that of ab initio calculations.