Expressions are given for analytic determination of energy second derivatives of closed-shell restricted Hartree-Fock (RHF) wave functions under the effect of an external uniform electric field. In this way, harmonic vibrational frequencies can be computed. Application of the theoretical method to the methane molecule is presented, and comparison with the induced changes in vibrational bands of its experimental infrared spectrum is carried out. © 1988 American Institute of Physics.
|Journal||The Journal of Chemical Physics|
|Publication status||Published - 1 Jan 1989|