Spectrum and Magnetic Properties of Hexagonal DyCl3

The absorption and fluorescence spectra of anhydrous DyCl3 were investigated and the levels up to 37 000 cm—1 above the ground state established. Conclusive evidence is presented that the levels below 15 000 cm—1 belong to the 6H and 6F multiplets. The Zeeman effects show considerable nonlinear interactions which follow quantitatively the existing theory. The 12 low levels and their electric and magnetic field splittings are reasonably well represented by the simplified theory with L-S coupling, with the approximate crystal parameters B20=A20〈r2〉 =89.8 cm—1, B40=—40.0 cm—1, B60=—23.3 cm—1, B66=253 cm—1.