Phase transition and relaxation processes by 87Rb and 39K nuclear magnetic measurements of RbKSO4 single crystals Original Research Article

87Rb and 39K nuclear magnetic resonance (NMR) spectra of RbKSO4 single crystals were measured at room temperature. 87Rb central line has the angular dependences of second-order quadrupolar shifts. From these results, the quadrupole coupling constant and the asymmetry parameter were determined at room temperature. In addition, the spin–lattice relaxation rate, 1/T1, and the spin–spin relaxation rate, 1/T2, were measured as a function of temperature. The values of 1/T1 for the 87Rb and 39K nuclei were found to increase with increasing temperature, and 1/T1 was determined to be proportional to Tn. Therefore, for the 87Rb and 39K nuclei, Raman processes with n=2 are more significantly in nuclear quadrupole relaxation than direct processes.