The diffusion coefficient was calculated on the basis of a Hamiltonian for coupled coherent and incoherent transport, with site-diagonal and off-diagonal stochastic fluctuations. The latter were not restricted to the usual white-noise expression for correlations between fluctuating variables. The result was applicable to any specific correlation, and allowed for long correlation times. Examples were given for monotonically decreasing and oscillating correlations. In the case of exponential decay of the correlations, the diffusion coefficient could be expressed in terms of complete elliptic integrals.

Diffusion Coefficient for Disordered Systems with Coupled Coherent and Incoherent Transport in One Dimension. W.Pfluegl, M.A.Palenberg, R.J.Silbey, Journal of Chemical Physics, 2000, 113[14], 5632-43