Electronic structures and spectral properties of rhenium(I) tricarbonyl diimine complexes with phosphine ligands: DFT/TDDFT theoretical investigations

► Four rhenium tricarbonyl complexes with phosphorus ligands were studied theoretically. ► The phosphine ligands have significant effects on geometric parameters. ► The lowest absorption bands of all complexes have 1MLCT/1LLCT transition characteristics. ► Complexes 1, 2 and 3 have characteristic of 3MLCT/3ILCT. ► Complex 4 only have 3ILCT characteristics.