NMR study of 133Cs in a singlet-ground-state system CsFeCl 3

To study spin dynamics and magnetic structure in the CsFeCl ₃ singlet-ground-state system, we have measured the temperature dependence of nuclear spin-lattice relaxation time T₁ and NMR spectrum of ¹³³Cs nuclear spin. From the experimental results of T₁^-1, we conclude that the softening of energy gap occurs under the magnetic field within the range of the present measurement. The experimental results of NMR spectrum left a problem in the ordered state.