We present a scaling theory for charge transport in disordered molecular semiconductors that extends percolation theory by including bonds with conductances close to the percolating one in the random-resistor network representing charge hopping. A general and compact expression is given for the charge mobility for Miller-Abrahams and Marcus hopping on different lattices with Gaussian energy disorder, with parameters determined from numerically exact results. The charge-concentration dependence is universal. The model-specific temperature dependence can be used to distinguish between the hopping models.
Cottaar, J., Koster, L. J. A., Coehoorn, R., & Bobbert, P. A. (2011). Scaling theory for percolative charge transport in disordered molecular semiconductors. Physical Review Letters, 107(13), 136601-1/4. . https://doi.org/10.1103/PhysRevLett.107.136601