Neutron-Scattering Study of the Ferroelectric Phase Transition in CsD2PO4

Abstract

A neutron-scattering study of the ferroelectric transition in Cs${\mathrm{D}}_2$P${\mathrm{O}}_4$ has yielded quasi-elastic diffuse distributions of intensity typical of a one-dimensional system with chain-like ordering parallel to the ferroelectric $b$ axis of this monoclinic crystal. Therefore, despite such suggestive similarities as the large isotope shift in $T_c$, the transition is quite different from that of tetragonal K${\mathrm{D}}_2$P${\mathrm{O}}_4$ where the diffuse scattering clearly exhibits characteristics of three-dimensional dipolar interactions.