IMPROVED METHOD OF CALCULATING GROUP POLARIZATION EFFECTS - CONSTANTSSIGMA(ALPHA)

An improved model is presented for ab initio calculations of the polar izability constants sigma(alpha) using Sadlej's basis set. A new set o f constants was calculated for common groups and these were compared w ith previous 3-21G and 3-21G* calculations and with some experimental equilibrium constants in the gas phase. For the time being, the calcul ations seem to be the most general approach for obtaining these consta nts whereas the experimental possibilities are limited in scope. (C) 1 998 John Wiley & Sons, Ltd.