The emissive T1 state is of 3 MLCT/LLCT character. The T1 state of complexes C4, C4N4 and C4N5 have almost equal contributions of HOMO-LUMO and HOMO-LUMO+1 transitions, while the remaining complexes have a T1 state dominated by the HOMO-LUMO+1 transition (see Table for tabulated excited state energies and transitions for all complexes).