Geminate recombination in high mobility

In this physical picture of geminate recombination in high-mobility systems, it is no longer valid to use the space criterion of reaction expressed in terms of the distance. Instead, the energy criterion of reaction expressed in terms of energy or, more preferably, the energy-dependent reaction cross section should be used. 

Computer simulation has also been used to calculate the external electric field effect on the geminate recombination in high-mobility systems [22]. For the mean free time x exceeding -0.05, the field dependence of the escape probability was found to significantly deviate from that obtained from the diffusion theory. Furthermore, the slope-to-intercept ratio of the field dependence of the escape probability was found to decrease with increasing x. Unlike in the diffusion-controlled geminate recombination, this ratio is no longer independent of the initial electron-ion separation [cf. Eq. (24)]. 

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