Azobenzene versus 3,3',5,5'-tetra-tert-butyl-azobenzene (TBA) at Au(111): Characterizing the role of spacer groups

Autor:	McNellis, Erik R., Bronner, Christopher, Meyer, Jorg, Weinelt, Martin, Tegeder, Petra, Reuter, Karsten
Rok vydání:	2010
Předmět:	Condensed Matter - Materials Science Condensed Matter - Mesoscale and Nanoscale Physics Condensed Matter - Other Condensed Matter Physics - Chemical Physics Physics - Computational Physics
Zdroj:	Phys. Chem. Chem. Phys. 12, 6404 (2010)
Druh dokumentu:	Working Paper
DOI:	10.1039/c001978j
Popis:	We present large-scale density-functional theory (DFT) calculations and temperature programmed desorption measurements to characterize the structural, energetic and vibrational properties of the functionalized molecular switch 3,3',5,5'-tetra-tert-butyl-azobenzene (TBA) adsorbed at Au(111). Particular emphasis is placed on exploring the accuracy of the semi-empirical dispersion correction approach to semi-local DFT (DFT-D) in accounting for the substantial van der Waals component in the surface chemical bond. In line with previous findings for benzene and pure azobenzene at coinage metal surfaces, DFT-D significantly overbinds the molecule, but seems to yield an accurate adsorption geometry as far as can be judged from the experimental data. Comparing the trans adsorption geometry of TBA and azobenzene at Au(111) reveals a remarkable insensitivity of the structural and vibrational properties of the -N=N- moiety. This questions the established view of the role of the bulky tert-butyl-spacer groups for the switching of TBA in terms of a mere geometric decoupling of the photochemically active diazo-bridge from the gold substrate. Comment: 9 pages including 6 figures; related publications can be found at http://www.fhi-berlin.mpg.de/th/th.html
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/1002.0687 Zobrazit plný text záznamu View this record from Arxiv