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A series of new 4‐hydroxy‐1,3‐thiazole‐based chromophores bearing different arylamine components (triarylamines, carbazole, and phenothiazine) as electron donors and azaheterocycle components (pyridine, pyrazine and pyrimidine) as electron‐acceptor moieties have been synthesized. Elaborate quantum chemical calculations were carried out with two selected compounds to identify the natures of the HOMO/LUMO transition and of the intramolecular charge‐transfer state. The electrochemical properties were investigated: the dyes show reversible first oxidation and reduction peaks, with the former strongly dominated by the type of arylamine. The donor moieties were synthesized under Buchwald–Hartwig conditions. Several of the presented X‐ray structures provide deeper insight into the geometries of the ligands. The bidentate nature of the chromophores makes them suitable as ligands in transition metal complexes. The corresponding ruthenium(II) polypyridine complexes – Ru(dmbpy)2(L)(PF6)2 (dmbpy = 4,4′‐dimethyl‐2,2′‐bipyridine) – were successfully synthesized for seven of the ligands. The MLCT bands in these complexes are significantly broadened, resulting in improved light‐harvesting efficiencies.

The semiconductor materials Si, SiC, GaP, InP, GaAs, and InAs were irradiated at normal incidence and room temperature with a focused Ga ϩ ion beam in order to investigate the damage production at high current densities on the order of some A cm Ϫ2 . The samples were irradiated with ion fluences between 2ϫ10 13 and 2ϫ10 15 Ga ϩ cm Ϫ2 at an ion energy of 50 keV. The critical ion fluences for amorphization were determined by Rutherford backscattering spectrometry and by Raman spectroscopy. It was found that for SiC, GaP, and InP the number of displacements per atom necessary for amorphization is about the same one as that required for irradiation at low current densities, but in the cases of Si, GaAs, and InAs the high and low current density results differ remarkably. The reason for the different behavior of these materials is discussed.

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