6533b829fe1ef96bd128a27f

RESEARCH PRODUCT

Antiferroelectric phase transition inRb3D(SO4)2single crystals studied by87RbNMR

Gerald HinzeA. TitzeRoland Böhmer

subject

PhysicsPhase transitionCrystallographyCondensed matter physicsProtonPhase (matter)Relaxation (NMR)QuadrupoleExponentResonanceMonoclinic crystal system

description

The quadrupole perturbed central transition of the magnetic ${}^{87}\mathrm{Rb}$ resonance was used to study ${\mathrm{Rb}}_{3}{\mathrm{D}(\mathrm{S}\mathrm{O}}_{4}{)}_{2}$ single crystals. Three resonance lines were found at room temperature. This result is in accord with the monoclinic space group reported for these crystals and does not require the previously invoked self-trapped proton states. The number of resonance lines quadruples below the antiferroelectric phase transition near 82 K. From the line splitting the order-parameter exponent of the low-temperature phase was found to be $\ensuremath{\beta}=0.2.$ Spin-lattice relaxation times have been determined in the fully protonated and deuterated disulfates and were used to deduce the temperature dependence of the order-parameter fluctuations.

https://doi.org/10.1103/physrevb.57.r666