Polypyridine Ruthenium(II) Complexes Containing Mixed Ligands. Synthesis, Spectroscopic and Photophysical and Electrochemical Properties

• Published in: Dyes and pigments 1998-04, Vol.37 (2), p.177-186
• Main Authors: Jing, Bing-wen, Wang, Wei-qin, Zhang, Man-hua, Shen, Tao
• Format: Article
• Language: English
• Subjects: charge–transfer transition; Chemistry; Coordination compounds; cyclic voltammetry; Exact sciences and technology; Inorganic chemistry and origins of life; polypyridine complex; Preparations and properties; Ruthenium(II); time-resolved emission Spectra
• ISSN: 0143-7208; 1873-3743
• DOI: 10.1016/S0143-7208(97)00057-0

A series of polypyridine Ruthenium(II) complexes Ru(II)(ttp)(L)X×PF 6 were synthesized and characterized, where L are 2,2′-bipyridine(bpy), 4,4′-dimethyl-2,2′-bipyridine(dmpy), 1,10-phenanthroline(phen) and X are Cl −, NCS −, CN −; ttp=4′-p-tolyl-2,2′:6′,2′′-terpyridine. Their redox, spectroscopic and photophysical properties have been studied. All complexes have intense MLCT(d M→π L*) absorbance at approximately 500 nm and were found to be emitting with monoexponential decay of emission intensity at 298 K. The maximum wavelengths of absorbance and emission undergo a blue shift in the order of Cl −, NCS −, CN −. All complexes have an one-electron-oxidative process corresponding to Ru(III)/Ru(II) with a potential of about 0.8 V, and their oxidation potential increased also according to Cl −, NCS −, CN −. Two reversible or quasi-reversible one-electron-reductive processes based on ligands were also observed.