On the thermal dependence of the twist viscosity in nematic liquid crystals

Abstract
We show that the twist viscosity γ1 of 4-methoxy-4' n butyl azoxybenzene varies according to the law : γ1 ∼ S exp(E/kT). Generalization to nematics with negative order parameter suggests that the relevant expression could be : γ1 ∼ |S| exp(E/kT)