TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Compound: The complex of formula (I) is preferably of formulae (IIa) or (IIb). For (IIa) M is Ru(II) or Os(II); X is NCS-, CN-; L is a ligand of formula (IIa'). For (IIb) M is Ru(II) or Os(II); X is NCS-, CN-; L is a ligand of formula (IIb').B1 and B2 = -COOH, -COON(C4H9)2, -PO(OH)2;C1 and C2 = H, 6-30C alkyl provided that one of C1 or C2 is not a hydrogen atom. Preferred Definitions:    M=Ru(II) or Os(II);    X=NCS- or CN-; and    L=polypyridine ligand of formula (IIa) or (IIb);    B1, B2=-COOH, -COON(C4H9)4, or -PO(OH)2; and    C1, C2=H or 6-30C alkyl    Any one of C1 and C2 is different from H. In (IIa): when C1 is H and C2 is nC11H23, B1 and B2 are COOH; when C1 is H and C2 is nC19H39, B1 and B2 are COOH; when C1 is H and C2 is nCH(C8H17)2, B1 and B2 are COOH; when C1 is H and C2 is nCH(C12H25)2, B1 and B2 are COOH; when C1 is C10H21 and C2 is nC11H23, B1 and B2 are COOH; when C1 is nC16H33 and C2 is nC19H39, B1 and B2 are COOH; when C1 is nC10H21 and C2 is nCH(C8H17)2, B1 and B2 are COOH; when C1 is nC16H33 and C2 is nCH(C12H25)2, B1 and B2 are COOH; when C1 is H and C2 is nC19H39, B1 and B2 are PO(OH)2; when C1 is nC10H21 and C2 is nC11H23, B1 and B2 are PO(OH)2; and when C1 is nC16H33 and C2 is nC19H39, B1 and B2 are PO(OH)2. In (IIb): when C1 is H and C2 is nC11H23, B1 and B2 are COOH; when C1 is H and C2 is nC19H39, B1 and B2 are COOH; when C1 is H and C2 is nCH(C12H25)2, B1 and B2 are COOH; when C1 and C2 are nC11H23, B1 and B2 are COOH; when C1 and C2 are nC19H39, B1 and B2 are COOH; when C1 is H and C2 is nC19H39, B1 and B2 are PO(OH)2; and when C1 and C2 are nC19H39, B1 and B2 are PO(OH)2.    EXAMPLE - Ru(p-cymene)Cl2 (61 mg) was dissolved in ethanol (50 ml). 4,4'-Diethoxycarbonyl-4"-hexadecyl-4'"-nonadecyl-2,2':6',2":6",2'"-quaterpyridine (100 ml) was added, and the mixture was refluxed for 6 hours. The black precipitate was filtered and washed with ethanol to yield Ru(4,4-diethoxycarbonyl-4"-hexadecyl-4'"-nonadecyl-2,2':6',2":6",2' "-quaterpyridine)Cl2 as dark powder (yield: 90%). Ammonium thiocyanate (350 mg) in water (10 ml) was added to a solution of complex Ru(4,4-diethoxycarbonyl-4"-hexadecyl-4'"-nonadecyl-2,2':6',2":6",2' "-quaterpyridine)Cl2 (100 mg) in dimethylformamide (50 ml). The reaction mixture was heated to 140degreesC for 3 hours. Triethylene nitride (10 ml) was added, and the solution was refluxed for additional 24 hours to hydrolyze the ester groups on the quaterpyridine ligand. the solution was cooled to room temperature. The black precipitate was filtered, washed thoroughly with water, and dried under vacuum to yield Ru(4,4'-dicarboxy-4"-hexadecyl-4'"-nonadecyl-2,2':6',2":6",2'"-quaterpyridine)NCS2 as dark powder (yield: 90%).