SCF calculations of the CH-stretching overtone intensities in dichloromethane within the local mode model

Oscillator strengths for the CH-stretching components of the overtone spectrum of dichloromethane are calculated for ΔvCH ≤4. The calculations use local mode theory to obtain the vibrational wave functions and SCF theory, with a number of different basis sets, to obtain the dipole moment functions. A comparison with experimental results shows the calculations can reproduce the relative ordering of the oscillator strengths as a function of the particular vibrational state, and give a reasonably quantitative account of the magnitude of the intensities, even with simple split-valence basis sets.