Can lattice models predict the density of states of amorphous organic semiconductors?

Phys Rev Lett. 2012 Sep 28;109(13):136401. doi: 10.1103/PhysRevLett.109.136401. Epub 2012 Sep 25.

Abstract

We extend existing lattice models of small-molecule amorphous semiconductors by accounting for changes in molecular polarizability upon charging or excitation. A compact expression of this contribution to the density of states is provided. Although the lattice model and the description based on a microscopic morphology both qualitatively predict an additional broadening, shift, and an exponential tail (traps) of the density of states, a quantitative agreement between the two cannot be achieved.