We report that self-sorting during self-organizing surface-initiated copolymerization (co-SOSIP) provides facile access to oriented multicomponent architectures. Alternate lateral and uniform axial self-sorting into formal supramolecular n/p-heterojunction photosystems is found to generate up to 40 times more photocurrent. More or less topological matching gives rise to alternate axial self-sorting into inactive charge-transfer complexes or uniform lateral sorting into the less active macrodomains, respectively. Experimental support for self-repair during co-SOSIP is reported. Initiators on the surface are shown to serve as templates for the self-sorting into multichannel architectures of freely variable composition.

Dithienylhexafluorocyclopentene with (R)- or (S)-N-phenylethylamide substituents formed rod-like and 0.2-1.0 microm-thick platelike crystals by sublimation; upon UV irradiation, the crystals bent concavely to the incident light and finally rolled crystals were obtained; the bent crystals were reconverted to flat crystals by visible light irradiation.

A combined theoretical and experimental study was performed on diarylethenes and diarylethene-capped sexithiophenes aiming at an improved understanding of the electrochemical and photochemical ring-opening and ring-closing mechanisms. Theoretical calculations, based on DFT and TDDFT, suggested that the spatial distribution and the occupancy of the frontier orbitals determine and control the diarylethenes’ ring-opening and ring-closing upon photoirradiation and electrochemical oxidation. Optimized geometries, potential energy surfaces, and activation energies between the open-ring and closed-ring forms were calculated for diarylethenes in the neutral ground state, excited states, and mono- and dicationic states. Analysis of the frontier orbitals was employed to understand the cyclization and cycloreversion of diarylethenes and to predict and explain the switching properties of diarylethene-capped sexithiophene molecular wires. The TDDFT data were verified with experimentally measured UV/vis spectra. The DFT calculations estimated open-shell ground states of diarylethene-capped sexithiophene dications, which were verified with EPR spectroscopy, and the broadening of the peaks in the EPR spectra were explained with the calculated singlet−triplet splitting. The good agreement of experiment and theory allows for the understanding of switching behavior of diarylethenes in solutions, in metal break junctions, in monolayers on metal surfaces, and as a part of complex organic molecular wires.

Photo-and electro-chromism of diarylethene modified ITO electrodes -towards molecular based read-write-erase information storage Areephong, J.; Browne, Wesley; Katsonis, N.; Feringa, B.L. Link to publication in University of Groningen/UMCG research database Citation for published version (APA): Areephong, J., Browne, W. R., Katsonis, N., & Feringa, B. L. (2006). Photo-and electro-chromism of diarylethene modified ITO electrodes -towards molecular based read-write-erase information storage.

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