Knowledge Bank

An iterative finite difference method has been employed to compute the complete harmonic force field of $H2O2$. The derived force constants are in essential agreement with previous $calculations(1)$ using Pulay’s force method. This suggests that the chosen configurations are well suited to determining the potential energy function of $H2O2$. Scaling the ab initio force field results in a good overall fit to the frequencies of $H2O2$ and $D2O2$. The interaction force constants involving the torsional mode are all calculated to be quite small, in agreement with our earlier $assumption(2)$ that these interaction force constants are zero. $\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}$P. Botschwina, W. Meyer, and A. M. Semkow, Chem. Phys. 15, 25 (1976). $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$J. D. Rogers and J. J. Hillman, J. Chem. Phys. 75, 1085 (1981); J. Chem. Phys. 76, 4046 (1982).