Vibrational intensities of F2CO, Cl2CO, and Br2CO

Abstract

The complete neglect of differential overlap (CNDO) approximate wavefunctions for Cl₂CO have been applied to the calculation of the derivatives of the dipole moment with respect to the symmetry coordinates. Although it was not possible to choose unique sets of derivatives in the A₁ and B₁ species, the acceptable experimental derivatives are very close in magnitude permitting a comparison and interpretation of these derivatives with those found previously for F₂CO. Differences in the derivatives of F₂CO and Cl₂CO are used to predict the preferred experimental derivatives for Br₂CO. The effect of d orbitals in the calculation of the Cl₂CO derivatives is examined. The experimental results for the out‐of‐plane CCl and CBr bends indicate that these derivatives are positive and opposite in sign to the in‐plane derivatives, although the Cl₂CO out‐of‐plane bending derivative is very close to zero.