CALCULATIONS OF THE SPECTRA AND ELECTRONIC-PROPERTIES OF SUBSTITUTED N,N-DIMETHYLANILINES

Calculations are reported on the structure, transition energies, and g round and excited state dipole moments of substituted N,N-dimethylanil ines using both the AM1 method and a version of the CNDO/S method. The former gives a reasonable structural correlation with crystallographi c data for N,N-dimethyl-4-nitroaniline and with data calculated at the ab initio level using a 3-21G basis set, but the excited state proper ties are unsatisfactory despite the use of a multielectron configurati on interaction treatment. The CNDO method appears to give a much bette r correlation with the experimental data, and both the transition ener gies and the large change in the magnitude of the dipole moments produ ced on excitation for these molecules are well reproduced.