We have studied the quasi-two-dimensional layered compound systems (C 2H5NH3)2Cd1-xMn xCl4 (0≤x≤1) by means of 1H nuclear magnetic resonance (NMR) measurements. In contrast to the case of the unmixed crystal compounds (x=0, 1) following a single-exponential type of the NMR spin-lattice relaxation, a stretched-exponential type of recovery, M(t)= M0[1-exp(-t/T1S)n], was necessary for the stoichiometric composition systems in addition to it, the exponent n depending on the randomly distributed paramagnetic Mn impurity concentration x. The spin-lattice relaxation rate T1S-1 thus obtained showed a maximum at a percolation threshold xc≈0.3, in agreement with a percolation theory of the paramagnetic impurity relaxation. The stacking dimensions of the paramagnetic ions were derived from the exponent n as a function of x.
- A. Perovskite-type layered compounds
- D. Percolation theory of paramagnetic impurity relaxation
- E. Nuclear magnetic resonance
ASJC Scopus subject areas
- Condensed Matter Physics
- Materials Chemistry