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arXiv · 1507.07428

Quasi one-Dimensional Band Dispersion and Metallization In long Range Ordered Polymeric wires

G. Vasseur·Y. Fagot-Revurat·M. Sicot·B. Kierren·L. Moreau·D. Malterre·L. Cardenas·G. Galeotti·J. Lipton-Duffin·F. Rosei·M. Di Giovannantonio·G. Contini·P. Le Fèvre·F. Bertran·L. Liang·V. Meunier·D. F. Perepichka
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Abstract

We study the electronic structure of an ordered array of poly(para-phenylene) chains produced by surface-catalyzed dehalogenative polymerization of 1,4-dibromobenzene on copper (110). The quantization of unoccupied molecular states is measured as a function of oligomer length by scanning tunneling spectroscopy, with Fermi level crossings observed for chains longer than ten phenyl rings. Angle-resolved photoelectron spectroscopy reveals a graphene-like quasi one-dimensional valence band as well as a direct gap of 1.15 eV, as the conduction band is partially filled through adsorption on the surface. Tight-binding modelling and ab initio density functional theory calculations lead to a full description of the organic band-structure, including the k dispersion, the gap size and electron charge transfer mechanisms which drive the system into metallic behaviour. Therefore the entire band structure of a carbon-based conducting wire has been fully determined. This may be taken as a fingerprint of {\pi}-conjugation of surface organic frameworks.

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G. Vasseur, Y. Fagot-Revurat, M. Sicot, B. Kierren, L. Moreau, D. Malterre, L. Cardenas, G. Galeotti, J. Lipton-Duffin, F. Rosei, M. Di Giovannantonio, G. Contini, P. Le Fèvre, F. Bertran, L. Liang, V. Meunier, D. F. Perepichka. 2015-07-27. Quasi one-Dimensional Band Dispersion and Metallization In long Range Ordered Polymeric wires. https://doi.org/10.1038/ncomms10235

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