The luminescence from heavily doped ZnSe:N shows a deep broadband whose position was found to depend strongly on the excitation intensity and sample temperature. The peak was found to shift towards higher energies with increasing intensity, but in contrast to the standard donor–acceptor pair (DAP) model, shifted towards lower energies with increasing temperatures. This behavior is explained using a modified DAP model that takes into account the perturbations of the band and impurity states caused by fluctuations in the concentrations of the ionized impurities. This model led to an estimate of 2.52 eV for the PL peak, with a width of 140 meV, for the case of low temperature and low excitation intensity, in rough agreement with our observations. The effect of these fluctuations on film conductivity is also discussed. ©1995 American Institute of Physics.