GROUND-STATE PROPERTIES OF TB3+ ION IN TBNI10SI2

Ground state properties of Tb3+ ion were investigated in the tetragona l ThMn12-type TbNi10Si2 compound on the basis of temperature dependenc e of the paramagnetic susceptibility and magnetization measurements. T he rare earth temperature dependence of the susceptibility was calcula ted using the Van Vleck equation. The Gamma(t5)((1)) doublet is sugges ted to be a ground state separated by 9 K from the first excited singl et Gamma(t1)((2)). The magnetic moment associated with the ground stat e doublet agrees with saturation magnetization data at 4.2 K. The over all crystal field splitting is estimated to be 105 K.