Abstract:  Modern experimental methods allow us to obtain reliable spectroscopic data for many systems of catalytic interest. These include gas phase and adsorbed / reacting molecules, as well as local sites at catalytic substrate surfaces and in the substrate bulk. Theoretical studies, based on density-functional theory (DFT) methods, can help to interpret corresponding experimental spectra and can provide an understanding of excitation phenomena and other physical behavior on a microscopic scale. This applies, in particular, to electron spectroscopy experiments using synchrotron radiation such as X-ray absorption (XAS/NEXAFS) or X-ray photoemission (XPS). This talk reviews recent theoretical work on electronic and structural properties, where spectroscopic data have been evaluated using DFT cluster methods together with gradient corrected functionals. Relevant computational strategies, using the StoBe code (Stockholm-Berlin collaboration), will be discussed and illustrated by examples from recent theoretical studies. These include phenyl propenes, C9H10, adsorbed at the Cu(111) surface [1], differently coordinated oxygen sites at transition metal oxide surfaces V2O5 [2], MoO3 [3], as well as supported vanadia and molybdena particles on SBA-15 silica [4, 5].

[1] C. Kolczewski, F. J. Williams, R. L. Cropley, O. P. H. Vaughan, A. J. Urquhart, M. S. Tikhov, R. M. Lambert, and K. Hermann, J. Chem. Phys. 125, 034701 (2006).
[2] C. Kolczewski and K. Hermann, Surf. Sci. 552, 98 (2004).
[3] M. Cavalleri, K. Hermann, S. Guimond, Y. Romanyshyn, H. Kuhlenbeck, and H.-J. Freund, Catalysis Today, 124, 21 (2007).
[4] M. Cavalleri, K. Hermann, A. Knop-Gericke, M. Hävecker, R. Herbert, C. Hess, A. Oesterreich, J. Döbler, and R. Schlögl, J. Catal. 262, 215 (2009).
[5] C. Guo, K. Hermann, M. Hävecker, L. J. Gregoriades, J. Sauer, A. Trunschke, and R. Schlögl, J. Phys. Chem. C 115, 15449 (2011).

DateTime: July 31, 2012 (Tuesday), 15:00 – 16:00
Location: 606 Conference Room