7Li NMR Studies of LiCrO2

Abstract

We report on 7 Li NMR studies of a spin S = 3/2 triangular lattice antiferromagnet LiCrO 2 (Néel temperature T N = 62 K) in the paramagnetic state by using the free-induction decay of 7 Li nuclear magnetization. We observed critical divergence of the 7 Li nuclear spin-lattice relaxation rate 1/T 1 near T N , a narrow critical region, and a critical exponent w = 0.45 from a fit of 1/T 1 ∝ (T /T N -1) −w . Although spin frustration effects have been explored for this system, the dynamical critical phenomena suggest that LiCrO 2 in the critical region is a poor low dimensional antiferromagnetic system.