Calculation of dipole hyperpolarizabilities of H2O, NH3, CH4 and CH3F

Abstract
From the first-order corrections of the SCF MO induced by a static homogeneous electric field, the third-order corrections to the SCF molecular energies have been evaluated. These SCF hyperpolarizabilities were determined, by using basis sets of STF of various sizes to express the unperturbed and the perturbed orbitals, for H2O, NH3, CH4 and CH3F. In some cases the calculated value compare badly with the experimental estimates. The possible reasons for these disagreement are briefly discussed.