NMR study of magnetic properties in SmRu4P12

P-31-NMR spectra and nuclear spin-lattice relaxation time T-1 have been measured in the temperature range between 4.2 and 300 K. NMR spectrum becomes suddenly broad below metal-insulator transition temperature (T-MI = 16.2 K), suggesting that SmRu4P12 shows magnetic phase transition just below T-MI. Relaxation rate 1/T-1 obeys the exponential relation (proportional toexp[-DeltaE/k(B)T]) with DeltaE/k(B) = 47 K below T-N. The NMR results around T-MI are discussed. (C) 2002 Elsevier Science B.V. All rights reserved.