We extend the standard random trapping (RT) model of electron transport ondhyphen;dimensional hypercubic lattices to include longhyphen;range charge transfer. We show that for RT models, it is possible to decouple exactly the site energy disorder from the distance dependence of the hopping rate. We then apply the exit probability approach developed by us to the formulation of the transport properties. At short times for exchangehyphen;type rates, we show that it is the site energy disorder rather than the distance dependence of the hopping rate that determines the shorthyphen;time dependence of the meanhyphen;square displacement. The analytic structure of the shorthyphen;time expansion is shown to be consistent with the corresponding limit of a typologically disordered random hopping problem. At long times we consider exchange and multipolar models for the hopping rates. For a particle initially placed at the origin, it is shown that the long behavior of the diffusion coefficient lsqb;D(t)minus;D(t=infin;)rsqb;sim;tminus;d/2, is identical to the asymptotic behavior ofD(t) for nearesthyphen;neighbor transport. The implications of these results on photoconductivity are discussed.
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