Electronic and photophysical properties of adducts of [Ru(bpy)(3)](2+) and Dawson-type sulfite polyoxomolybdates alpha/beta-[Mo(18)O(54)(SO(3))(2)](4-)

James Walsh, De-Liang Long, Leroy Cronin, Alan Bond, Robert Forster, Tia Keyes

Research output: Contribution to journalArticleResearchpeer-review

34 Citations (Scopus)

Abstract

The spectroscopic and photophysical properties of [Ru(bpy)(3)](2)[[Mo(18)O(54)(SO(3))(2)], where bpy is 2,2 -bipyridyl and [Mo(18)O(54)(SO(3))(2)](4-) is either the alpha or beta-sulfite containing polyoxomolybdate isomer, have been measured and compared with those for the well known but structurally distinct sulfate analogue, alpha-[Mo(18)O(54)(SO(4))(2)](4-). Electronic difference spectroscopy revealed the presence of new spectral features around 480 nm, although they are weak in comparison with the [Ru(bpy)(3)](2)[Mo(18)O(54)(SO(4))(2)] analogue. Surprisingly, Stern-Volmer plots of [Ru(bpy)(3)](2+) luminescence quenching by the polyoxometallate revealed the presence of both static and dynamic quenching for both alpha and beta-[Mo(18)O(54)(SO(3))(2)](4-). The association constant inferred for the ion cluster [Ru(bpy)(3)](2)alpha-[Mo(18)O(54)(SO(4))(2)] is K = 5.9 +/- 0.56 x 10(6) and that for [Ru(bpy)(3)](2)beta-[Mo(18)O(54)(SO(4))(2)] is K = 1.0 +/- 0.09 x 10(7). Unlike the sulfate polyoxometalates, both sulfite polyoxometalate-ruthenium adducts are non-luminescent.
Original languageEnglish
Pages (from-to)2038 - 2045
Number of pages8
JournalDalton Transactions
Volume40
Issue number9
DOIs
Publication statusPublished - 2011

Cite this