Structure of the <i>f</i>6 Configuration with Application to Rare-Earth Ions

Abstract

Free-ion energy-level schemes for the 4f6 and 4f8 configurations of Eu3+, Sm2+, and Tb3+ are given, which have been calculated from energy matrices including interactions among the three highest multiplicities. The values obtained for the parameters are F2 = 401 cm—1, ζ = 1320 cm—1 for Eu3+; F2 = 330 cm—1, ζ = 1050 cm—1 for Sm2+; and F2 = 434 cm—1, ζ = 1705 cm—1 for Tb3+. The wavefunctions and g values for levels to 40 000 cm—1 are tabulated for Eu3+ and Tb3+. Application of the free-ion wavefunctions to the Stark splitting of EuCl3 and TbCl3 is discussed.