Calculation of Crystal-Field Splittings of Sm3+ and Dy3+ Levels in LaCl3 with Inclusion of J Mixing

Abstract

Calculations of the crystal‐field splitting of the low lying sextet multiplets of the f⁵ and f⁹ configurations in a field of C_3h symmetry have been performed and the results are compared to experimental data on Sm³⁺ and Dy³⁺ in LaCl₃. The effect of inclusion of terms coupling different free ion J manifolds is examined, and several interesting features which arise from this effect are discussed. For Sm³⁺ 39 observed crystal‐field levels are reproduced with a standard deviation of ±3.2 cm^—1 with the crystal‐field parameters B₂⁰ = A₂⁰〈r²〉 = 80.85 cm^—1, B₄⁰ = —22.75 cm^—1, B₆⁰ = —44.39 cm^—1, and B₆⁶ = 425.7 cm^—1. For Dy³⁺ 39 observed levels are reproduced with a standard deviation of ±2.7 cm^—1 with the parameters B₂⁰ = 91.30 cm^—1, B₄⁰ = —38.97 cm^—1, B₆⁰ = —23.17 cm^—1, and B₆⁶ = 257.8 cm^—1. The remaining small discrepancies between calculated and observed levels can probably be attributed to inadequate free‐ion wave functions.