Diffuse X-Ray Scattering in Random Mixture of Ferroelectric and Antiferroelectric: Rb_1−x(NH₄)_xH₂PO₄

Abstract

The measurement of the diffuse X-ray scattering in a random mixture of ferroelectric RbH₂PO₄ (RDP) and antiferroelectric NH₄H₂PO₄ (ADP), (RDP)_1−x(ADP)_x, has been carefully carried out. The equi-intensity contours of the diffuse scattering observed in glassy (RDP)_0.3(ADP)_0.7 is similar to that in antiferroelectric (RDP)_0.15(ADP)_0.85 near the Neel temperature, implying that there are small antiferroelectric clusters in the glassy phase of the antiferroelectric side. But the temperature dependence of the scattering intensity in the glassy phase is distinctly different from that in the antiferroelectric phase.