RANDOM-WALK MODEL WITH CORRELATED JUMPS - SELF-CORRELATION FUNCTION AND FREQUENCY-DEPENDENT DIFFUSION-COEFFICIENT

In this paper we report the results of a generalization of the continuous-time random walk theory of Montroll and Weiss to include correlations over two jumps. We expand our results of a previous letter by discussing the multi-state master equation formulation for Bravais and non-Bravais lattices. We present results for these equations and discuss the ease of tetrahedral interstitial sites in body centered cubic lattices which have a realization in hydrogen in metal systems. We prove that the Bravais lattices always reduce to a second-order differential equation and we give a general solution for the frequency-dependent diffusion coefficient in this case. © 1979.