Radical ion pair mediated triplet formation in polymer-fullerene blend films

Efficient triplet formation is observed for films of high ionisation potential polythiophenes blended with a fullerene derivative, and assigned to formation via geminate charge recombination of bound radical ion pair states.     

Single-molecule electrical studies on a 7 nm long molecular wire

A self-assembled arylene-ethynylene molecular wire with a rigid 7 nm long backbone exhibits symmetrical current-voltage (I-V) characteristics and a single-molecule current of 0.35 +/- 0.05 nA at 0.3 V; these data are supported by theoretical calculations.     

Synthesis of 2-pyranosyl benzothiazoles, benzimidazoles and benzoxazoles via nucleophilic addition reactions of pyranosyl nitrile oxides

Reaction of per-O-acetylated-β-d-pyranosyl nitrile oxides, generated by dehydrochlorination of the corresponding hydroximoyl chlorides, with 2-aminothiophenol afforded 2-(β-d-pyranosyl)benzothiazoles. 1,2-Diaminobenzene and 2-aminophenol reacted similarly to yield 2-(β-d-pyranosyl)benzimidazoles and 2-(β-d-pyranosyl)benzoxazoles, respectively. The structures of 2-β-d-glucopyranosylbenzimidazole (17), 2-(2,3,4-tri-O-acetyl-β-d-xylopyranosyl)benzimidazole (19) and the xylopyranosyl thiohydroximate 13 were established by X-ray crystallography.     

Renormalisation group improved leptogenesis in family symmetry models

We study renormalisation group (RG) corrections relevant for leptogenesis in the case of family symmetry models such as the Altarelli–Feruglio A₄$A_4$ model of tri-bimaximal lepton mixing or its extension to tri-maximal mixing. Such corrections are particularly relevant since in large classes of family symmetry models, to leading order, the CP violating parameters of leptogenesis would be identically zero at the family symmetry breaking scale, due to the form dominance property. We find that RG corrections violate form dominance and enable such models to yield viable leptogenesis at the scale of right-handed neutrino masses. More generally, the results of this paper show that RG corrections to leptogenesis cannot be ignored for any family symmetry model involving sizeable neutrino and τ Yukawa couplings.