title: Dynamical disorder of pi-molecular structures induced by proton dynamics in an organic ferroelectric compound.
abstract: We have investigated the optical response resulting from the proton-pi-electron-molecular-skeleton coupled dynamics in an organic ferroelectric 55DMBP-Hia. Upon the ferroelectric-to-paraelectric transition, almost all of the vibrational modes below 500 cm;{-1} are anomalously blurred and amalgamated into the high-frequency tail of the polarization-relaxation mode. This indicates that the constituent molecular shape is no more well defined around T_{C} due to the dynamical disorder of the pi-conjugated structure originating from proton delocalization on the intermolecular bifurcated hydrogen bond.
authors.affiliation: Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan.
authors.forename: J
authors.initials: J
authors.lastname: Fujioka
authors.forename: S
authors.initials: S
authors.lastname: Horiuchi
authors.forename: F
authors.initials: F
authors.lastname: Kagawa
authors.forename: Y
authors.initials: Y
authors.lastname: Tokura