The J-mixing effect in Ln3+ ions crystal field levels

Hydrothermal crystallization of a Ln2(OH)4SO4·nH2O layered compound for a wide range of Ln (Ln = La–Dy), thermolysis, and facile transformation into oxysulfate and oxysulfide phosphors

“…The Eu 3+ ions in Gd 2 O 2 SO 4 and Gd 2 O 2 S present the low-site C 1 and C 3v symmetries, respectively, and thus a stronger electric dipole 5 D 0 / 7 F 2 transition than magnetic dipole 5 D 0 / 7 F 1 transition was observed for both the cases. 21,45 The PLE spectrum of (Gd 0.99 Tb 0.01 ) 2 O 2 SO 4 (l em ¼ 545 nm, Fig. 8c) presents several sharp peaks in the $200-325 nm region, with the 8 S 7/2 / 6 I J transition of Gd 3+ at 275 nm being the strongest.…”

Critical analysis of the limitations of Bleaney's theory of magnetic anisotropy in paramagnetic lanthanide coordination complexes

“…However, the Russell–Saunders coupling scheme may not be appropriate for these relatively heavy elements and the values of the spin–orbit coupling energies (typically of the order of 650 to 1800 cm –1 ), are not much bigger than the overall ligand field splitting terms in some cases, in complexes where the ligand field is large. In this situation, the concept of ‘ J mixing’ is often invoked, 9 , 10 as a means of correcting for, or simply recognising imprecision in J . The measurements of Sessoli were carried out in the solid state at cryogenic temperatures.…”

“…The series of complexes, [Ln.L [6][7][8][9] ] have lower time-averaged symmetry and allow a comparison of 9-coordinate (q ¼ 1) carboxylate systems with 8-coordinate (q ¼ 0) phosphinate analogues. In the complexes of L 6 , a CF 3 group is located 6.1 Å from the metal centre, 19 whereas in the other three cases a t Bu group is 6.6 (AE0.2) Å distant, each separated by 5 bonds.…”

Interpretation of europium(III) spectra

“…Even in strong magnetic fields, the splitting of the energy levels by the Zeeman effect is only a few cm -1 .The J quantum numbers are well defined in the free Eu 3+ ion, but J-mixing occurs when the Eu 3+ is located in a non-spherically symmetric ligand environment (vide infra) [107,108]. J-mixing is induced by the even-parity components of the crystal-field potential.…”