Transport properties of MoS<Subscript>2</Subscript> nanoribbons: edge priority

We report about results from density functional based calculations on structural, electronic and transport properties of one-dimensional MoS₂ nanoribbons with different widths and passivation of their edges. The edge passivation influences the electronic and transport properties of the nanoribbons. This holds especially for nanoribbons with zigzag edges. Nearly independent from the passivation the armchair MoS₂ nanoribbons are semiconductors and their band gaps exhibit an almost constant value of 0.42 eV. Our results illustrate clearly the edge priority on the electronic properties of MoS₂ nanoribbons and indicate problems for doping of MoS₂ nanoribbons.     

Hydrogen-bond acceptance of bifunctional ligands in an alkyne-metal pi complex

Experiment and theory have been used to study reactive alkyne pi complexes, intermediates in anti-Markovnikov alkyne hydration by CpRu bis(phosphine) catalysts with heterocyclic substituents. Each heterocycle accepts a hydrogen bond from an acetylene C-H, as revealed by NMR coupling constants between alkyne 13C and 1H nuclei as well as between alkyne 13C and pyridine 15N (2hJCN). Moreover, further alkyne transformations occur at temperatures from 50 to 90 degrees C below what is needed to convert a control compound without the heterocycles.