Abstract: A material comprising an electron-accepting unit of formula (I): wherein Ar1 and Ar2 independently is a 5- or 6-membered aromatic or heteroaromatic ring or is absent; and each X is independently H or a substituent with the proviso that at least one X is an electron-withdrawing group and wherein X groups bound to adjacent carbon atoms may be linked to form an electron-withdrawing group. The material further comprises an electron-donating unit D comprising a fused or unfused furan or thiophene. The material may be a polymer comprising repeat units of formula (I). The material may be a non-polymeric compound. An organic photodetector may contain a bulk heterojunction layer containing an electron acceptor or an electron donor wherein at least one of the electron acceptor and electron donor contains a unit of formula (I).

Abstract: A material comprising a group of formula (I): (I) wherein: X and Y are each independently selected from S, O or Se; Ar1, Ar2, Ar3 and Ar4 are each independently an unsubstituted or a substituted benzene, an unsubstituted or a substituted 5- or 6-membered heteroaromatic group or are absent; A1 and A2 are each independently an unsubstituted or a substituted benzene, an unsubstituted or a substituted 5- or 6-membered heteroaromatic group, a non-aromatic 6-membered ring having ring atoms selected from C, N, S and O or are absent; R1 is H or a substituent; R2 and R3 are each independently H or a substituent; and * represents a point of attachment to a hydrogen or non-hydrogen substituent.

Abstract: A process for the preparation of a complex of formula (I): the process comprising the step of reacting a complex of formula (II) or a complex of formula RuX3.H2O (IV) with a bidentate ligand of formula (III) wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, A, B, and X are described in the specification; the molar ratio of the complex of formula (II): the bidentate ligand of formula (III) is about 1:6 to about 1:8 or the molar ratio of the complex of formula (IV): the bidentate ligand of formula (III) is about 1:3 to about 1:4; and the process is carried out in water or a water-based solvent, wherein the water-based solvent comprises at least 60% water (by volume) and an organic solvent, at one or more temperatures in the range of about 80° C. to 110° C.