Abstract: A compound of formula (I): (Core)n-(X)m wherein Core is a core group; n is 0 and m is 1, or n is 1 and m is at least 1; and X is a group of formula (II): wherein: R1, R3 and R5 are each independently H or a substituent; R2 and R4 are each a substituent; one of R1-R5 is a direct bond or divalent linking group linking the group of formula (II) to Core in the case where n is 1; x and y are 0, 1, 2, 3 or 4; and the compound of formula (I) is substituted with at least one ionic substituent. The compound may be used as an n-dopant to dope an organic semiconductor.

Abstract: A charge-transfer salt formed from a material comprising a repeat unit of formula (I) and an n-dopant: wherein BG is a backbone group of the repeat unit; R1 is a ionic substituent comprising at least one cationic or anionic group; n is at least 1; R2 is a non-ionic substituent; and m is 0 or a positive integer; the material further comprising a counterion balancing the charge of the cationic or anionic group.

Abstract: A compound of formula (I) or (III) (Formulae (I), (III)) wherein: one Y is a substituent R1 bound directly to the fluorene unit of formula (I) by an sp3-hybridised carbon atom; the other Y is an aryl or heteroaryl group Ar1 that may be unsubstituted or substituted with one or more substituents; Ar2 is an arylene or heteroarylene group; R2 is a substituent; b is 0, 1, 2, 3 or 4; c is 0, 1, 2 or 3; and X is a group of formula (II): (Formula (II)) wherein Z is O or S; R3 independently in each occurrence is a substituent; each x is independently 0, 1, 2 or 3; and * is a bond to the fluorene unit of formula (I). The compounds may be used as host materials for phosphorescent dopants in organic light-emitting devices.

Abstract: An organic photodetector comprising a first electrode, a second electrode, and a photosensitive organic layer between the electrodes, the photosensitive organic layer comprising a donor polymer and an acceptor compound, characterized in that the acceptor compound has a LUMO level shallower than that of the fullerene derivative PCBM.

Abstract: Light-Emitting Compound A composition comprising a light-emitting compound having a peak wavelength of at least 650 nm and a material comprising a group of formula (I): wherein Ar1, Ar2 and Ar3 in each occurrence are independently selected from a C6-20 aromatic group and a 6-20 membered heteroaromatic group of C and N ring atoms and at least one of Ar1, Ar2 and Ar3 is a 6-20 membered heteroaromatic group of C and N ring atoms; x, y and z are each independently at least 1; n, m and p are each independently 0 or a positive integer; and R1, R2 and R3 in each occurrence is independently a substituent or a single bond to a polymer chain, wherein the group of formula (I) has no more than 3 single bonds to a polymer chain. The composition may be used in the light-emitting layer of an infrared organic light-emitting device.

Abstract: A polymer containing an optionally substituted repeat unit of formula (I) wherein each R is the same or different and represents H or an electron withdrawing group, and each R1 is the same or different and represents a substituent.

Abstract: A compound of formula (I) wherein Z is a group of formula (II) and Core is selected from groups of formula (IIIa) or (IIIb) wherein X is S or O; R1 is a substituent; n is 0 or a positive integer; Ar1 independently in each occurrence is an arylene group; R2 is a substituent; R3 is a substituent; R4 is an arylene or heteroarylene group; Y is C or Si; a is 1, 2 or 3; b is 0 or a positive integer; and c is 0 or a positive integer. The compound of formula (I) may be used as a host for a light-emitting dopant in an organic light-emitting device.

Abstract: A charge-transfer salt formed from a material comprising a repeat unit of formula (I) and an n-dopant: wherein BG is a backbone group of the repeat unit; R1 is a ionic substituent comprising at least one cationic or anionic group; n is at least 1; R2 is a non-ionic substituent; and m is 0 or a positive integer; the material further comprising a counterion balancing the charge of the cationic or anionic group.

Abstract: An organic photodetector (OPD) comprises a microcavity defined by a reflective electrode and a semi-transparent electrode, wherein the microcavity comprises a transparent conductive oxide layer and an active layer comprising an n-type organic semiconductor and a p-type organic semiconductor, and wherein the blend of the n-type organic semiconductor and the p-type organic semiconductor exhibits low absorption at the resonance wavelength, which results in an excellent optical sensitivity in a favorably narrow wavelength region and allows to tune the response to different wavelengths depending on the desired application. In addition, methods of producing such organic photodetectors and methods of tuning the resonance of a microcavity formed in an organic photodetector (OPD) to a predetermined wavelength are provided.

Abstract: A compound represented by the formula (1) is provided: wherein A1 represents an oxygen atom, a sulfur atom, —NR5— or —PR5—; at least one A1 is —NR5— or —PR5—; R1 represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryloxy group, an alkylsulfenyl group, a cycloalkylsulfenyl group, an arylsulfenyl group or a disubstituted amino group; R2 and R3 represent an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group, a cycloalkoxy group, an aryloxy group, an alkylsulfenyl group, a cycloalkylsulfenyl group, an arylsulfenyl group, a monovalent heterocyclic group, a halogen atom or a disubstituted amino group; R4 represents a hydrogen atom, —C(R6)3, —OR7, —N(R7)2 or —Si(R7)3; m represents an integer of 0 to 3; and n represents an integer of 0 to 4.

Abstract: A compound of formula (I): wherein M is a transition metal; x is at least 1; z is 0 or a positive integer; L1 is a ligand selected from one of ligands (II-A), (II-B); L2 is a ligand selected from another of ligands of formulae (II-A), (II-B) and (II-C); and L3 is a ligand other than a ligand of formulae (II-A), (II-B) or (II-C): (II-A) (II-B) (II-C) in which each of R1-R6 is substituent and Ar1-Ar3 are each an unsubstituted or substituted aryl or heteroaryl group. The compound of formula (I) may be used as a phosphorescent light-emitting material of an organic light-emitting device.

Abstract: Organic Light-Emitting Device An organic light-emitting device (100) comprising an anode (103); a cathode (109); a light-emitting layer (107) between the anode and the cathode; and a hole-transporting layer (105) between the anode and the cathode, wherein the light-emitting layer comprises a light-emitting compound of formula (I) and the hole-transporting layer comprises a hole-transporting material having a HOMO level that is no more than 5.1 e V from vacuum level: N N ML x R 2 (R) m (R) n y (I) wherein: R in each occurrence is independently a substituent; R 2 is H or a substituent; m is 0, 1 or 2; n is 0, 1, 2, 3 or 4; M is a transition metal; L is a ligand; y is at least 1; and x is 0 or a positive integer.

Abstract: A device for optically exciting fluorescence is disclosed. The device comprises transparent substrate having first and second opposite faces and a multilayer stack disposed on the second face of the substrate. The multilayer stack comprises a first layer having first and second opposite faces and a first refractive index and a second layer having first and second opposite faces and a second refractive index. The first face of the first layer is disposed on the second face of the substrate. The first face of the second layer is disposed on the second face of the first layer such that the first layer is interposed between the second layer and the substrate. The substrate has a third refractive index. The first refractive index is less than the second refractive index and the third refractive index. The device comprises a light source carried by the first face of the substrate and arranged to emit light towards the first face of the first layer.

Abstract: Light-emitting composition and devices including the same, the composition including a fluorescent light-emitting material and a polymer having a conjugating repeat unit and a non-conjugating repeat unit in a backbone of the polymer, and in which the conjugating repeat unit provides at least one conjugation path between repeat units linked to it; the non-conjugating repeat unit reduces conjugation of the polymer as compared to a polymer in which the non-conjugating repeat unit is absent; and a triplet excited state energy level of the light-emitting material is higher than a triplet excited state energy level of the non-conjugating repeat unit.

Abstract: A light-emitting polymer comprising a light-emitting repeat unit in a backbone of the polymer, wherein the polymer has an anisotropy of no more than 0.8 and wherein a transition dipole moment of the light-emitting repeat unit is aligned with the polymer backbone.

Abstract: An organic photodetector comprising a first electrode, a second electrode, and a photosensitive organic layer between the electrodes, the photosensitive organic layer comprising a donor polymer and an acceptor compound, characterized in that the acceptor compound has a LUMO level shallower than that of the fullerene derivative PCBM.

Abstract: A polymer comprising a repeat unit of formula (I): (I) wherein each Ar1 and each Ar2 independently represents a substituted or unsubstituted aromatic or heteroaromatic group; each Cy independently represents a saturated heterocyclic or carbocyclic ring that may be unsubstituted or substituted with one or more substituents; n is 1, 2 or 3; and adjacent groups Ar2 may be linked by a divalent linking group in the case where n is 2 or 3. The polymer may be used as a charge-transporting material or light-emitting material in an organic light-emitting device.

Abstract: A light-emitting polymer comprising a light-emitting repeat unit in a backbone of the polymer, wherein the polymer has an anisotropy of no more than 0.8 and wherein a transition dipole moment of the light-emitting repeat unit is aligned with the polymer backbone.

Abstract: An organic light emitting device which emits white light in use, comprising a reflective anode (3), a first light emitting layer (9) which emits red light located over said anode, a second light emitting layer (11) which emits blue light and green light located over said first light emitting layer, and a cathode structure located over said second light emitting layer comprising a first semi-reflecting layer (15) and a second semi-reflecting layer (21) with a layer (19) of light transmissive material between the first and second semi-reflecting semi-transparent layers, the distance between the reflective anode (3) and the first semi-reflecting semi-transparent layer (17) being selected to form a micro-cavity which enhances blue light emission and red light emission from the device, and the distance between the reflective anode (3) and the second semi-reflecting semi-transparent layer (21) being selected to enhance green light emission from the device.

Abstract: A compound of formula (I): wherein M is a transition metal; x is at least 1; z is 0 or a positive integer; L1 is a ligand selected from one of ligands (II-A), (II-B); L2 is a ligand selected from another of ligands of formulae (II-A), (II-B) and (II-C); and L3 is a ligand other than a ligand of formulae (II-A), (II-B) or (II-C): (II-A) (II-B) (II-C) in which each of R1-R6 is substituent and Ar1-Ar3 are each an unsubstituted or substituted aryl or heteroaryl group. The compound of formula (I) may be used as a phosphorescent light-emitting material of an organic light-emitting device.