Original scientific paper

Synthesis and Photochemical Properties of RuII and RuII-OsII Complexes with a Long Bridging Ligand of Tetrapyridobiphenazine

Zainul Abedin Siddique ; Department of Chemistry, Chittagong University, Chittagong-4331, Bangladesh
Kajuyoshi Miyawaki ; Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka-560, Japan
Takeshi Ohnob ; Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka-560, Japan

Abstract

Semi rigid tetradentate p-conjugated bridging ligand, tetrapyridobiphenazine (tpbpz), its mono
and binuclear complexes of ruthenium(II) and ruthenium(II)-osmium(II) have been synthesized.
The ligand has chelation sites separated by 2.1 nm. Photochemical properties of these
complexes have been investigated using time-resolved laser spectroscopy. In the RuII-OsII
heteronuclear complex, intramolecular energy transfer occurs from a metal-to-ligand charge
transfer (MLCT) state of the RuII moiety, i.e., (3CT)Ru, to the second metal site, i.e., OsII. Molar
absorption coefficient differences (Dees) along with the excited state formation were determined
using an energy transfer method from the triplet metal-to-ligand charge transfer state
(3MLCT) of the complex to anthracene. Quantitative conversion of RuII-OsII compound to
RuII-OsIII was performed by means of electrochemistry.

Keywords

photochemical property; Ru-Os complexes

Hrčak ID:

31136

URI

https://hrcak.srce.hr/31136

Publication date:

15.11.2008.

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