Figure 6.

Pre-edge regions of the Ln³⁺ L₃-edge absorptions (Ln = La, Ce, Pr, Nd, Pm, Sm, and Eu) were obtained by the integration of the calculated 2p3d RIXS planes along the Y-axis. The curves are shown in a unified energy scale, with zero corresponding to the position of the white line. For Pm, the energy of the pre-edge feature was set to fit the data for the other lanthanides. A₁ and A₂ labels represent low- and high-energy quadrupolar features, respectively (left panel). The energy separation between the A₁ and A₂ features across the series was derived by the integration of the calculated 2p3d RIXS plane along the energy-transfer axis. Theoretical data from ref (56) are shown by open circles. Dashed lines are guides to the eye.