THE CONTRIBUTION FROM SPIN-ORBIT-COUPLING OF LIGAND IONS TO G-FACTORSIN VCL2 AND VBR2

This paper presents a two-so-coupling-parameter model, in which not on ly the contribution due to the so coupling of the central Tm ions but also that of the ligand ions are included, for the calculation of the g-factors and the anisotropy DELTAg(= g(z) - g(x)) of the trigonal d3 cluster. The calculated results for VCl2 and VBr2 show that the contri bution to both g and DELTAg due to the so coupling of the ligand ions is small in VCl2 but is sufficiently important in VBr2, about 85% for g and 40% for DELTAg. It suggests that in the calculation of g and DEL TAg the two-so-coupling-parameter model should be preferred in the cas e of heavy-element ligand ions such as Br- ions.