Distinct roles of the triplicated ZnCl4 tetrahedra in phase soliton formation and residual commensurations in K2ZnCl4

The dynamics of the ZnCl4 tetrahedra, in the ferroelectric lock-in phase of K2ZnCl4 was studied by means of pulsed Cl-35 NQR (nuclear quadrupole reson ance) techniques. From the temperature dependence of the spin-lattice relax ation rate (1/T-1Q) for each of the triplicated Cl(1) sites in the lock-in phase, it is suggested that the domain peak in the incommensurate phase ari ses from the ZnCl4 tetrahedral site with a negligible reorientational motio n, whereas the other two sites with an activated reorientational motion lea d to the phase solitons.