Spinmdash;Lattice Relaxation of Rh(II) in Single Crystals of ZnWO4

摘要

The spinhyphen;lattice relaxation timeT1of Rh(II) in a single crystal of ZnWO4has been measured in the temperature range 1.5deg;mdash;110deg;K. In the region 56deg;mdash;110deg;K relaxation occurs by an Orbach process. From the temperature dependence of this process, the separation of the first excited Kramers doubletEprime; from the ground doubletEPrime; is found to be 320 cmminus;1, and the lifetime of the excited state 1.7times;10minus;11sec. At low temperatures, the relaxation times are relatively short and depend upon the direction of the applied magnetic fieldH.WithHaligned along thea, b,orccrystalline axes an anomalously strong dependence ofT1on temperature is observed.