Figure 4.

RIXS spectra excited at 932.4 eV (933.4 eV) in left (right) panel. Red (blue) lines are spectra recorded at room temperature (at 15 K). Corresponding model calculations using the indicated ground state configurations: 3d¹⁰L⁻¹ (magenta), 3d⁸L⁺¹ (black), and 3d⁹L^±1 (green). In the lower (upper) part of the panel, in-plane, E||ab (out-of-plane, E||c), polarized x-rays have been used for excitation.