Simultaneous control of spectroscopic and electrochemical properties in functionalised electrochemiluminescent tris(2,2′-bipyridine)ruthenium(ii) complexes
- 1 January 2011
- journal article
- Published by Royal Society of Chemistry (RSC) in The Analyst
- Vol. 136 (7), 1329-1338
- https://doi.org/10.1039/c0an00952k
Abstract
Using a combination of electrochemical, spectroscopic and computational techniques, we have explored the fundamental properties of a series of ruthenium diimine complexes designed for coupling with other molecules or surfaces for electrochemiluminescence (ECL) sensing applications. With appropriate choice of ligand functionality, it is possible to manipulate emission wavelengths while keeping the redox ability of the complex relatively constant. DFT calculations show that in the case of electron withdrawing substituents such as ester or amide, the excited state is located on the substituted bipyridine ligand whereas in the case of alkyl functionality it is localised on a bipyridine. The factors that dictate annihilation ECL efficiency are interrelated. For example, the same factors that determine ΔG for the annihilation reaction (i.e. the relative energies of the HOMO and LUMO) have a corresponding effect on the energy of the excited state product. As a result, most of the complexes populate the excited state with an efficiency (Φex) of close to 80% despite the relatively wide range of emission maxima. The quantum yield of emission (Φp) and the possibility of competing side reactions are found to be the main determinants of ECL intensity.Keywords
This publication has 69 references indexed in Scilit:
- A new hybrid DFT approach to electronic excitation and first hyperpolarizabilities of transition metal complexesJournal of Computational Chemistry, 2009
- Ruthenium polypyridyl chemistry; from basic research to applications and back againDalton Transactions, 2006
- Electrogenerated chemiluminescence detection for deoxyribonucleic acid hybridization based on gold nanoparticles carrying multiple probesAnalytica Chimica Acta, 2006
- Solar Energy Conversion by Dye-Sensitized Photovoltaic CellsInorganic Chemistry, 2005
- Extremely high stereoselectivity of novel helical ruthenium(II) complexes for photoinduced reduction of racemic-[Co(acac)3] (Hacacpentane-2,4-dione)Journal of Photochemistry and Photobiology A: Chemistry, 1996
- An Efficient Preparation of 4, 4′-Dicarboxy-2, 2′-BipyridineSynthetic Communications, 1995
- Synthesis of polypyridyl complexes of ruthenium(II) containing three different bidentate ligandsInorganic Chemistry, 1992
- Synthesis of 4,4′‐divinyl‐2,2′‐bipyridineJournal of Heterocyclic Chemistry, 1990
- Energy-adjustedab initio pseudopotentials for the second and third row transition elementsTheoretical Chemistry Accounts, 1990
- Synthesis of side-chain derivatives of 2,2'-bipyridineThe Journal of Organic Chemistry, 1989