ISSN:
0020-7608
Keywords:
Computational Chemistry and Molecular Modeling
;
Atomic, Molecular and Optical Physics
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Traditionally, the calculation of the vibrational spectra of molecules involves at one point or another a numerical differentiation procedure. Such a method has some serious drawbacks both in efficiency and in accuracy. In this paper, an alternative method based on linear response theory is presented. The second derivative of the ground-state energy is expressed in terms of the electron density response matrix by means of perturbation theory. The unperturbed wave functions are obtained from the Hartree-Fock equation. First-order perturbation theory applied to this equation leads to the Hartree-Fock linear response. As an illustration of this method the vibrational frequency of a H2 molecule is calculated. The result is 1.348 × 1014 Hz as compared to the experimental value of 1.319 × 1014 Hz. This method is also applicable in the calculation of the phonon dispersion curves of solids.
Additional Material:
1 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/qua.560180144
