Magnetic susceptibilities of trivalent lanthanide ions in an octahedral environment

Magnetic susceptibilities for eight lanthanide ions in Cs2NaLnCl6 were measured from 2.5 to [inverted lazy s] 80°K with a vibrating sample magnetometer. Computer fitting of the data for Cs2NaCeCl6 gave g = 1.43 for the Γ7 ground level, and f2 = 3.85 for the Γ8 excited level. These values are in good agreement with values calculated from first-order wavefunctions. The ground crystal field level for Nd3+ in Cs2NaNdCl6 was found to be a Γ8 level. Because of singlet ground levels and small crystal field splitting, no positive information on the ground crystal field levels was obtained for Pr3+, Tb3+, Dy3+, Ho3+, Er3+, or Tm3+ compounds. Based on Nd3+ and Ce3+ results, the ratio A40 /A60 was estimated to be about 20; A40 , of the order of 10 cm−1; and A60 , of the order of 1 cm−1.