The ferroelectric fluctuation in KD2PO4

Abstract

Measurement and analysis of diffuse X-ray scattering, and a re-analysis of earlier neutron scattering measurements, from the ferroelectric fluctuation just above T_c in KD₂PO₄ have established that this fluctuation has an acoustic mode component which is polarised along the ferroelectric axis. This effect accounts for the recently noted discrepancy between the atomic motions implied by structural studies and those derived in all previous studies of the ferroelectric scattering.