A compound of formula wherein: - m, n, p and q are independently selected from an integer from 0 to 3; - R 1 and R 2 are substituents independently selected from H, C1-C35 alkyl, C4-C35 aryl, C1-C35 arylalkyl, C4-C35 heteroaryl, wherein heteroatoms are selected from O, S or N; - R 1 and R 2 are substituents independently selected from H, OH, S, =O (keto group), C1-C35 alkyl, C1-C35 thioalkyl, C1-C35 alkoxy, C4-C35 aryl, C1-C35 arylalkyl, C4-C35 heteroaryl, wherein heteroatoms are selected from O, S or N; - Ar 1 and Ar 2 are different from each other and Ar 1 and Ar 2 are aromatic aryl groups independently selected from a moiety according to any one of formula to: wherein R 3 is selected from H, C1-C35 alkyl, C4-C35 aryl, C1-C35 arylalkyl, or C4-C35 heteroaryl, wherein the heteroatoms are selected from O, S, or N; - Π-Spacer 1 and Π-Spacer 2 are independently selected from a moiety according to any one of formula to: wherein R 4 is selected from H, C1-C35 alkyl, C1-C35 alkoxy, C1-C35 thioalkyl, C4-C35 aryl, C1-C35 arylalkyl or C4-C35 heteroaryl, wherein heteroatoms are selected from O, S, or N; - A is a substituent comprising an anchoring group "Anch" and an acceptor group and being selected from a moiety according to any one of formula to: wherein R 5 is selected from H, C1-C35 alkyl, C1-C35 alkoxy, C1-C35 thioalkyl, C4-C35 aryl, C1-C35 arylalkyl or C4-C35 heteroaryl, wherein heteroatoms are selected from O, S, or N and Anch is an anchoring group independently selected from -COOH, PO 3 H 2, -PO 4 H 2, -P(R 8)O 2 H, -SO 3 H 2, - SO 4 H 2, -CONHOH -, 1,2-hydroxybenzene, 1-hydroxy-2-carboxybenzene, acetylacetonate, deprotonated forms of the aforementioned, organic and /or inorganic salts of said deprotonated forms, wherein R 8 is a hydrocarbon comprising from 1 to 50 carbons and 0-25 heteroatoms selected from O, N, or S, said hydrocarbon being covalently bound to the P atom of said phosphinic acid group by a carbon atom; - D is a donor group selected from a moiety according to any one of formula to: wherein R 6 is selected from H, C1-C35 alkyl, C1-C35 alkoxy, C1-C35 thioalkyl, C4-C35 aryl, C1-C60 arylalkyl or C4-C35 heteroaryl, wherein heteroatoms are selected from O, S, or N and wherein aryl is optionally substituted by C4-C35 arylalkyl or by C4-C35 arylalkoxy groups; - Ar 3 and Ar 4 are aromatic aryl groups independently selected from a moiety according to any one of formula to: wherein R 7 is selected from H, C1-C35 alkyl, C4-C35 aryl, C1-C35 arylalkyl, or C4-C35 heteroaryl, wherein the heteroatoms are selected from O, S, or N; - and wherein said C1-C35 alkyl, C1-C35 alkoxy, C1-C35 thioalkyl, C4-C35 aryl, C1-C35 arylalkyl or C4-C35 heteroaryl may be further substituted or unsubstituted by a C1-C11 hydrocarbon comprising 0 to 15 heteroatoms selected from O, N, S or halogen. - m, n, p and q are independently selected from an integer from 0 to 3; - R 1 and R 2 are substituents independently selected from H, C1-C35 alkyl, C4-C35 aryl, C1-C35 arylalkyl, C4-C35 heteroaryl, wherein heteroatoms are selected from O, S or N; - R 1 and R 2 are substituents independently selected from H, OH, S, =O (keto group), C1-C35 alkyl, C1-C35 thioalkyl, C1-C35 alkoxy, C4-C35 aryl, C1-C35 arylalkyl, C4-C35 heteroaryl, wherein heteroatoms are selected from O, S or N; - Ar 1 and Ar 2 are different from each other and Ar 1 and Ar 2 are aromatic aryl groups independently selected from a moiety according to any one of formula to: wherein R 3 is selected from H, C1-C35 alkyl, C4-C35 aryl, C1-C35 arylalkyl, or C4-C35 heteroaryl, wherein the heteroatoms are selected from O, S, or N; - Π-Spacer 1 and Π-Spacer 2 are independently selected from a moiety according to any one of formula to: wherein R 4 is selected from H, C1-C35 alkyl, C1-C35 alkoxy, C1-C35 thioalkyl, C4-C35 aryl, C1-C35 arylalkyl or C4-C35 heteroaryl, wherein heteroatoms are selected from O, S, or N; - A is a substituent comprising an anchoring group "Anch" and an acceptor group and being selected from a moiety according to any one of formula to: wherein R 5 is selected from H, C1-C35 alkyl, C1-C35 alkoxy, C1-C35 thioalkyl, C4-C35 aryl, C1-C35 arylalkyl or C4-C35 heteroaryl, wherein heteroatoms are selected from O, S, or N and Anch is an anchoring group independently selected from -COOH, PO 3 H 2, -PO 4 H 2, -P(R 8)O 2 H, -SO 3 H 2, - SO 4 H 2, -CONHOH -, 1,2-hydroxybenzene, 1-hydroxy-2-carboxybenzene, acetylacetonate, deprotonated forms of the aforementioned, organic and /or inorganic salts of said deprotonated forms, wherein R 8 is a hydrocarbon comprising from 1 to 50 carbons and 0-25 heteroatoms selected from O, N, or S, said hydrocarbon being covalently bound to the P atom of said phosphinic acid group by a carbon atom; - D is a donor group selected from a moiety according to any one of formula to: wherein R 6 is selected from H, C1-C35 alkyl, C1-C35 alkoxy, C1-C35 thioalkyl, C4-C35 aryl, C1-C60 arylalkyl or C4-C35 heteroaryl, wherein heteroatoms are selected from O, S, or N and wherein aryl is optionally substituted by C4-C35 arylalkyl or by C4-C35 arylalkoxy groups; - Ar 3 and Ar 4 are aromatic aryl groups independently selected from a moiety according to any one of formula to: wherein R 7 is selected from H, C1-C35 alkyl, C4-C35 aryl, C1-C35 arylalkyl, or C4-C35 heteroaryl, wherein the heteroatoms are selected from O, S, or N; - and wherein said C1-C35 alkyl, C1-C35 alkoxy, C1-C35 thioalkyl, C4-C35 aryl, C1-C35 arylalkyl or C4-C35 heteroaryl may be further substituted or unsubstituted by a C1-C11 hydrocarbon comprising 0 to 15 heteroatoms selected from O, N, S or halogen.