We studied the carriers generated in regioregular poly(3-hexylthiophene) (P3HT) upon FeCl3 vapor and solution doping using visible/near-infrared (VIS/NIR) absorption, infrared (IR), and Raman spectroscopy. Upon doping with an FeCl3 solution in air, the main carriers that were generated were positive polarons. Upon doping with FeCl3 vapor, positive polarons also formed initially, but at higher doping levels, positive bipolarons formed with the concomitant disappearance of the positive polarons. The Raman and IR spectra of the positive bipolarons and the positive polarons were obtained. Raman spectroscopy is very useful for characterizing positive polarons and bipolarons. The Raman results indicated that the positive bipolarons were converted to polarons upon heating to 85 °C, indicating that the positive bipolarons formed a metastable state. The temporal changes in the electrical conductivity of a P3HT film upon doping with FeCl3 vapor were measured. The conductivity reached a maximum and then decreased by 2 orders of magnitude. This result suggests that the mobility of the polarons is approximately 100 times as high as that of the bipolarons.

Interparticle forces in a nematic liquid-crystal colloid have been directly observed by the dual beam laser trapping method with pN sensitivity. We introduce two different types of spatial distributions of forces, detected between the particles accompanied by hyperbolic hedgehog defects. These force distributions lead to specific particle arrangements, which are both stabilized by the balance of the orientational stress field of nematics. On the basis of these results, we propose novel artificial construction for multiparticle regular arrangements.

Complex fluids are usually produced by mixing together several distinct components, the interactions between which can give rise to unusual optical and rheological properties of the system as a whole. For example, the properties of microemulsions (composed of water, oil and surfactants) are determined by the microscopic structural organization of the fluid that occurs owing to phase separation of the component elements. Here we investigate the effect of introducing an additional organizing factor into such a fluid system, by replacing the oil component of a conventional water-in-oil microemulsion with an intrinsically anisotropic fluid--a nematic liquid crystal. As with the conventional case, the fluid phase-separates into an emulsion of water microdroplets (stabilized by the surfactant as inverse micelles) dispersed in the 'oil' phase. But the properties are further influenced by a significant directional coupling between the liquid-crystal molecules and the surfactant tails that emerge (essentially radially) from the micelles. The result is a modified bulk-liquid crystal that is an ordered nematic at the mesoscopic level, but which does not exhibit the strong light scattering generally associated with bulk nematic order: the bulk material here is essentially isotropic and thus transparent.

The caption of Figure 4 in article adma.201300776 is hereby corrected to: Emission spectra at 30 °C (a) for a CLC shell of DBR mode (R = 107 µm, a = 72 µm) and (b) for a CLC shell of DFB mode (R = 107 µm, a = 92 µm) by pulsed pumping laser light of wavelengths of 450 nm and 510 nm, respectively. Broken lines in (a) and (b) are RB dissolved in water and emission spectra for DCM dissolved in ZLI2293, respectively. The insets in (a) and (b) show the emitted intensity at wavelengths of 619 nm and 566 nm for DBR and DFB mode lasings of CLC shells, respectively.

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