ligand to ligand charge transfer (LLCT) transition

https://doi.org/10.1351/goldbook.L03519
An electronic transition of a metal complex that corresponds to excitation populating an @ET07026@ in which considerable @E02011@ between two @L03518@ has occurred.
Source:
PAC, 1996, 68, 2223. (Glossary of terms used in photochemistry (IUPAC Recommendations 1996)) on page 2252 [Terms] [Paper]