Pinto, Nicholas J.Howell, Francis L.Schmidt, V. Hugo2016-04-152016-04-151993-09-01N.J. Pinto, F.L. Howell, and V.H. Schmidt, “Deuteron NMR study of dynamics and of coexistence of paraelectric and ferroelectric phases in Rb0.90(ND4)0.10D2AsO4,” Phys. Rev. B 48, 5983-5896 (1993).1098-0121https://scholarworks.montana.edu/handle/1/9690The deuteron glass Rb1−x(ND4)xD2AsO4 (DRADA) is a mixed crystal of RbD2AsO4 (DRDA) and ND4D2AsO4 (DADA). Deuteron nuclear magnetic resonance has been performed on the acid and ammonium deuterons. The crystal studied has an ammonium concentration (x=0.10) that puts it in the coexistence region of the phase diagram. Line-shape measurements of the ammonium deuterons show the coexistence of the ferroelectric (FE) and paraelectric (PE) phases as the temperature is lowered below the ferroelectric-phase-transition temperature Tc. The acid deuteron line shape on the other hand is found to broaden as the temperature is reduced but is unaffected by the ferroelectric transition. Spin-lattice-relaxation measurements have been performed and the activation energies for the relaxation processes have been computed. The relaxation-rate anomaly for acid deuterons in the ferroelectric-transition range indicates a short correlation length for the FE phase in the coexistence region of the phase diagram.Article