A Highly Disordered New Solid Phase Containing Isotropically Reorienting Cations in (CH3NH3)2CdBr4 Studied by l U NMR and Thermal Measurements
نویسندگان
چکیده
The 'H spin-lattice relaxation time, linewidth, second moment of 'H NMR absorption, differential thermal analysis, and differential scanning calorimetry of methylammonium tetrabromocadomate(II) crystals were studied. A new solid phase was found between 482 K and the melting point (493 K). The 'H NMR measurements revealed the presence of overall reorientation of methylammonium cations in this phase. In the room temperature phase, 120° reorientational jumps of the CH3 and NH 3 groups were detected.
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