We analyze the influence of strong electron-phonon coupling and thermal fluctuations on the Hall effect in organic crystals, using a variant of the Kubo formula. The Hall effect in organic crystals cannot simply be understood based on a band picture, but it is governed by competition between intermolecular quantum coherence and dynamic lattice disorder. When the intermolecular electronic coupling strength is comparable to that of rubrene crystals, delocalized Peierls polarons exhibit the Hall effect overcoming dephasing due to thermal fluctuations. As the electronic coupling decreases, the Peierls polaron is less delocalized, and the Hall effect is diminished by the dephasing. As the temperature decreases, the dephasing is suppressed and the Hall effect is enhanced, as is observed for pentacene crystals.

• Received 10 October 2012

DOI:https://doi.org/10.1103/PhysRevB.87.155305