Photoactive Metal-to-Ligand Charge Transfer Excited States in 3d6 Complexes with Cr0, MnI, FeII, and CoIII

compounds, for which long-lived MLCT states have become accessible over the past five years. Furthermore, we discuss possible future developments in the search for new first-row transition metal complexes with partially filled 3d subshells and photoactive MLCT states for next-generation applications in photophysics and photochemistry.