✦ LIBER ✦

Tuning of the CT excited state and validity of the energy gap law in mixed ligand complexes of Ru(II) containing 4,4′-dicarboxy-2,2′-bipyridine

✍ Scribed by K. Kalyanasundaram; Md.K. Nazeeruddin

Publisher: Elsevier Science
Year: 1992
Tongue: English
Weight: 577 KB
Volume: 193
Category: Article
ISSN: 0009-2614
DOI: 10.1016/0009-2614(92)85670-6

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✦ Synopsis

Using a series of electron-donating ligands (non-chromophoric or substituted bpy/phen type) the energy of the charge transfer (CT) transition has been varied systematically in mixed ligand complexes of Ru(II), [ Ru(dcbpy),(LL)

In all cases the lowest energy transition is Ruddcbpy CT. The lowering of the CT state energy is caused mainly by increased charge density at the Ru center (tZg level). A comparison of the spectral shift with redox potentials shows that nearly 25% of the increased charge density at the Ru-center is transferred to the dcbpy ligand via mixing of the dn-n* orbitals. The variation in the emission lifetimes and quantum yields in this graded series of complexes is quantitatively interpreted in terms of the energy gap law.