121Sb-NMR studies of single-crystal PrOs4Sb12

Abstract 121 Sb nuclear magnetic resonance (NMR) measurements have been carried out on a single-crystalline PrOs 4 Sb 12 for magnetic field ( H ) up to 15 T. A well-split 121 Sb-NMR spectrum was observed for H ∥ 〈 0 0 1 〉 . We calculated the electric field gradient (EFG) of Sb site by a FLAPW method based on LDA. We have identified the observed NMR lines corresponding to three different Sb sites with asymmetric EFG tensors.