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The electronic version of this article is the complete one and can be found online at: http://link.springer.com/article/10.1186/1556-276X-7-233 ; We fabricate freely suspended nanosheets of molybdenum disulphide (MoS2) which are characterized by quantitative optical microscopy and high-resolution friction force microscopy. We study the elastic deformation of freely suspended nanosheets of MoS2 using an atomic force microscope. The Young's modulus and the initial pre-tension of the nanosheets are determined by performing a nanoscopic version of a bending test experiment. MoS2 sheets show high elasticity and an extremely high Young's modulus (0.30 TPa, 50% larger than steel). These results make them a potential alternative to graphene in applications requiring flexible semiconductor materials ; This work was supported by MICINN (Spain) through the programs MAT2008-01735, MAT2011-25046 and CONSOLIDER-INGENIO-2010 'Nanociencia Molecular' CSD-2007-00010, Comunidad de Madrid through program Nanobiomagnet S2009/MAT-1726, and the European Union (FP7) through the program RODIN

Controlling the bandstructure through local-strain engineering is an exciting avenue for tailoring optoelectronic properties of materials at the nanoscale. Atomically thin materials are particularly well-suited for this purpose because they can withstand extreme nonhomogeneous deformations before rupture. Here, we study the effect of large localized strain in the electronic bandstructure of atomically thin MoS2. Using photoluminescence imaging, we observe a strain-induced reduction of the direct bandgap and funneling of photogenerated excitons toward regions of higher strain. To understand these results, we develop a nonuniform tight-binding model to calculate the electronic properties of MoS2 nanolayers with complex and realistic local strain geometries, finding good agreement with our experimental results. © 2013 American Chemical Society. ; This work was supported by the European Union (FP7) through the program RODIN and the Dutch organization for Fundamental Research on Matter (FOM). A.C.-G. acknowledges financial support through the FP7-Marie Curie Project PIEF-GA-2011- 300802 ("STRENGTHNANO"). R.R. acknowledges financial support from the Juan de la Cierva Program (MINECO, Spain). E.C. acknowledges financial support through the FP7-Marie Curie Project PIEF-GA-2009-251904. F.G. and R.R. acknowledge support from MINECO (Spain), through grant FIS2011-23713 and ERC Advanced grant no. 290846. ; Peer Reviewed

The bowl-shaped, 3-fold interlinked porphyrin dimer 2 was obtained in respectable yields during macrocyclization attempts. Its bicyclic structure, consisting of a macrocycle made of a pair of acetylene interlinked tetraphenylporphyrins which are additionally linked by a C-C bond interlinking two pyrrole subunits, has been confirmed spectroscopically (2D-NMR, UV/vis, HR-MALDI-ToF MS). Late-stage functionalization provided the structural analogue 1 with acetyl-protected terminal thiol anchor groups enabling single molecule transport investigations in a mechanically controlled break junction experiment. The formation of single-molecule junctions was observed, displaying large variations in the observed conductance values pointing at a rich diversity in the molecular junctions. ; European Union (EU): SEP 210165479. FET open project QuIET: 767187. Swiss National Science Foundation (SNSF): 200020-178808. Ministry of Education, China - 111 Project: 90002-18011002. Comisión Nacional de Investigación Científica y Tecnológica (CONICYT), CONICYT FONDECYT: 1181080.

We present experimental and theoretical studies of single-molecule conductance through nonplanar fullerocurcuminoid molecular dyads in ambient conditions using the mechanically controllable break junction technique. We show that molecular dyads with bare fullerenes form configurations with conductance features related to different transport channels within the molecules, as identified with filtering and clustering methods. The primary channel corresponds to charge transport through the methylthio-terminated backbone. Additional low-conductance channels involve one backbone side and the fullerene. In fullerenes with four additional equatorial diethyl malonate groups attached to them, the latter transport pathway is blocked. Density functional theory calculations corroborate the experimental observations. In combination with nonequilibrium green functions, the conductance values of the fullerocurcuminoid backbones are found to be similar to those of a planar curcuminoid molecule without a fullerene attached. In the nonplanar fullerocurcuminoid systems, the highest-conductance peak occurs partly through space, compensating for the charge delocalization loss present in the curcuminoid system. ; European Commission (COST Action MOLSPIN) CA1S128 European Commission (EU RISE (DAFNEOX) project) SEP-210165479 Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT) CONICYT FONDECYT 1181080 1161775 1170524 Fondequip EQM140055 EQM180009 NLHPC ECM -02 MICIIN PGC2018-093863-B-C21 Maria de Maeztu Excellence grant MDM-2017-0767 Generalitat de Catalunya 2017SGR1289 2017SGR1277 Netherlands Organization for Scientific Research (NWO) Spanish Government M.AT2016-778S2-C2-1-R Severo Ochoa Program for Centers of Excellence in RD SEV-2015-0496 European Research Council (ERC) 724981 National Science Foundation (NSF) CHE-1801317 The Welch Foundation AH-0033

Biological electron transport is classically thought to occur over nanometre distances, yet recent studies suggest that electrical currents can run along centimetre-long cable bacteria. The phenomenon remains elusive, however, as currents have not been directly measured, nor have the conductive structures been identified. Here we demonstrate that cable bacteria conduct electrons over centimetre distances via highly conductive fibres embedded in the cell envelope. Direct electrode measurements reveal nanoampere currents in intact filaments up to 10.1 mm long (>2000 adjacent cells). A network of parallel periplasmic fibres displays a high conductivity (up to 79 S cm(-1)), explaining currents measured through intact filaments. Conductance rapidly declines upon exposure to air, but remains stable under vacuum, demonstrating that charge transfer is electronic rather than ionic. Our finding of a biological structure that efficiently guides electrical currents over long distances greatly expands the paradigm of biological charge transport and could enable new bio-electronic applications. ; This research was financially supported by the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013) through ERC Grant 306933 (F.J.R.M.), the Research Foundation Flanders (FWO project grant G031416N), and the Netherlands Organisation for Scientific Research (VICI grant 016.VICI.170.072 to F.J.R.M.). H.J.E.B., C.J.B. and H.S.J.Z. were supported by the Netherlands Organisation for Scientific Research (NWO/OCW), as part of the Frontiers of Nanoscience program. R.B. is supported by an 'aspirant' grant from Research Foundation Flanders (FWO). We thank Laurine Burdorf (UAntwerpen) for help with Thiothrix cultivation, Marlies Nijemeisland (Faculty of Aerospace, TU Delft) for assistance with Raman microscopy, and Jan D'Haen (UHasselt) and Renaat Dasseville (UGent) for help with EM imaging.