Charge transport mechanism in high-mobility organic semiconductors
In plain words
In organic crystals such as rubrene, charges move in a way that fits neither the picture of free electrons in a metal nor that of hops between fixed molecules. A complete theory that predicts the measured mobility (how fast charges drift in an electric field) is missing.
Precise statement
For high-mobility organic semiconductors (rubrene, pentacene, C8-BTBT) at 100 to 300 K, with transfer integrals of order 0.1 eV comparable to thermal fluctuations of these integrals, predict the mobility $\mu(T)$ (measured about 3e3 to 1.2e4 $\mathrm{cm}^2/(\mathrm{statvolt}\ \mathrm{s})$ at room temperature in rubrene single crystals, lower in pentacene and C8-BTBT) and its temperature dependence from a microscopic model with ab initio parameters, deciding between transient localization, small-polaron and band pictures. An answer is a theory reproducing $\mu(T)$ and the Hall and terahertz data.
What would settle it
Ab initio parametrized nonadiabatic or quantum transport calculations reproducing mobility, Hall effect and optical conductivity on single crystals.