Excited electronic and ionized states of N,N-dimethylnitramine

Forty-five singlet, triplet and ionized states of the N,N-dimethylnitramine (DMNA) molecule, (CH3)2NNO2, a simple model of energetic materials, were computed using the symmetry-adapted-cluster/configuration interaction (SAC-CI) wave function. Vertical oscillator strengths, excitation energies and ionization intensities were calculated. Fine details of the experimental absorption ultraviolet (UV) and ionization spectra were successfully reproduced. Quantitative assignment of unresolved bands was proposed.