FisMat2017 - Submission - View

Abstract's title: Chemisorption of Pentacene on Pt(111) with a Little Molecular Distortion
Submitting author: Aldo Ugolotti
Affiliation: Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca
Affiliation Address: via Cozzi 55, 20125 Milano
Country: Italy
Oral presentation/Poster (Author's request): Oral presentation
Other authors and affiliations: Shashank S. Harivyasi (Institute of Solid State Physics, NAWI Graz, Graz University of Technology, Petersgasse 16, 8010 Graz, Austria), Anu Baby (Dipartimento di Scienze dei Materiali, Università degli Studi di Milano-Bicocca, via Cozzi 55, 20125, Milano, Italy), Marcos Dominguez (CNR-IOM, Laboratorio TASC, Basovizza SS-14, km 163.5, I-34149, Trieste, Italy and Dipartimento di Fisica, Università degli Studi di Trieste, via Valerio 2, 34127, Trieste, Italy), Anna Lisa Pinardi (Materials Science Factory, Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC), Sor Juana Inés de la Cruz 3, E-28049 Madrid, Spain), Maria Francisca López (Materials Science Factory, Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC), Sor Juana Inés de la Cruz 3, E-28049 Madrid, Spain), José Ángel Martı́n-Gago (Materials Science Factory, Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC), Sor Juana Inés de la Cruz 3, E-28049 Madrid, Spain), Guido Fratesi (Dipartimento di Fisica, Università degli Studi di Milano, via Celoria 16, 20133, Milano,Italy), L. Floreano (CNR-IOM, Laboratorio TASC, Basovizza SS-14, km 163.5, I-34149, Trieste, Italy), Gian Paolo Brivio (Dipartimento di Scienze dei Materiali, Università degli Studi di Milano-Bicocca, via Cozzi 55, 20125, Milano, Italy)
Abstract

We investigated the adsorption of pentacene on the (111) surface of platinum, which is an archetypal system for a junction with a low charge-injection barrier. We probed the structural and electronic configurations of pentacene by scanning tunnelling microscopy (STM), X-ray
photoemission spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy measurements. We simulated the interface by means of ab initio methods based on the density functional theory (DFT) framework, while including the dispersion forces. We found that the molecules adsorb at the bridge site of the close-compact atom rows with the long axis parallel to the substrate's <110> directions, in a slightly distorted geometry, driven by the good match between the position of carbon atoms of the molecule and the underlying lattice of the surface. Most importantly, a chemical bond is formed at the interface which we attribute to the high chemical reactivity of the Pt substrate.