Spectroscopy of self-trapped charge-transfer excitons in polar films and crystals of N,N-dimethylaminobenzylidene 1,3-indandione (DMABI)

The origin of exciton states in crystals built up by dipolar N,N-dimethylaminobenzylidene 1,3-indandione (DMABI) molecules has been investigated by means of absorption and luminescence spectroscopy. The exciton spectral and dynamical properties in the solid state are compared to those of the excitation of separated DMABI molecules embedded in a rigid polymer matrix. The luminescence excitation spectra and the luminescence decay kinetics are discussed on the basis of the specific adiabatic potential-energy scheme of the self-trapped excitons.