Calculation of frequency-dependent polarizabilities for open-shell systems at the second-order M�ller-Plesset perturbation theory level based on the quasi-energy derivative method

Abstract

We extended the dynamic response theory in the Møller–Plesset perturbation theory (MPPT) based on the quasi-energy derivative (QED) method for closed-shell systems to that for open-shell systems. In this study we perform the calculations of frequency-dependent polarizabilities α(−ω; ω) for nondegenerate open-shell doublet systems (Li, Na, and K atoms and BeH, MgH, CaH, CN, and NH2 molecules) in the second-order Møller–Plesset perturbation theory (MP2) starting with time-dependent restricted open-shell Hartree–Fock (TDROHF) approximation. © 1997 John Wiley & Sons, Inc. Int J Quant Chem 65: 665–677, 1997