| abstract |
A compound of formula (I): (X) n RuLL 1 where n is 1 or 2, preferably 2, and in which Ru is ruthenium; each X independently is selected from Cl, SCN, H 2 O, Br, I, CN and SeCN and L is a ligand of formulae (a) to (g) and L 1 is selected from a ligand of formulae (a) to (c) where each R independently is selected from OH, hydrogen, C 1-20 alkyl, --OR a or --N(R a ) 2 and each R a independently is hydrogen or C 1-4 alkyl. |