LAUSR

Abstract Seven novel binuclear Pt(II) metalated complexes based on substituted 3,6-diphenylpyridazines have been synthesized and structurally characterized using XRD crystallography, NMR spectroscopy and HR ESI mass-spectrometry. Three of these complexes contain two {Pt(CˆN)} metalated fragments located at diphenylpyridazine, the square-planar environment at platinum centres are completed with two terminal and one bridging chloride ligands. Substitution of terminal chlorides for various phosphines gave another group of complexes, which keep intact the metalated moieties and bridging chloride to form essentially similar structural motif. The compounds obtained display relatively weak green-orange phosphorescence in organic solvents with the quantum yield ranging from 1.0 to 3.4% in degassed solution. The experimental photophysical data and results of TDDFT calculations indicate that the observed emission occurs from the excited states of the mixed IL/MLCT nature, the contribution of the former dominates in chloride complexes, whereas in the phosphine derivatives the MLCT component of the emissive state shows considerable growth without visible variations in emission energy.