BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Memento EPFL// BEGIN:VEVENT SUMMARY:New Perspectives in Dynamics at Surfaces DTSTART:20131107T163000 DTEND:20131107T173000 DTSTAMP:20260406T161412Z UID:772507d42d5b145850b6dda20cbbf04943a4ffd4ad9860979d2516a8 CATEGORIES:Conferences - Seminars DESCRIPTION:Prof. Alec M. WodtkeGeorg-August University of Göttingen and the Max Planck Institute for Biophysical Chemistry\, Göttingen\, German y\nGreat strides in our understanding of surface chemistry have been achie ved over the last two decades due to the advent of computational methods t hat rely on the Born-Oppenheimer Approximation and exploit the power of th e many advances coming from electronic structure theory. However\, describ ing and understanding the atomic scale motion taking place during surface chemical events remains a daunting challenge. Many experiments now show th e breakdown of the Born Oppenheimer Approximation for molecular interactio ns at metal surfaces. This suggests that while energetics derived from mod ern computational approaches may be reasonably accurate\, characterizing t he atomic scale motion involved in surface chemical reactions is still an unsolved problem.\nIn this lecture I will describe experiments capable of revealing dynamical fingerprints of molecular interactions at surfaces whe re the Born-Oppenheimer Approximation fails.\nOne of the most powerful exp erimental tools at our disposal is a form of double resonance spectroscopy \, which allows us to define the quantum state of the molecule and measure its velocity both before and after the collision with the surface\, provi ding a complete picture of the resulting energy conversion processes takin g place between the molecule and the solid. With such data\, we are able t o emphasize quantitative measurements that can be directly compared to fir st principles theories that go beyond the Born-Oppenheimer approximation.\ nOne important outcome of this work is the realization that Born-Oppenheim er breakdown can be induced by simple charge transfer reactions that are c ommon in surface chemistry. Using a newly developed method to control mole cular orientation\, we are able to observe the orientation dependence of a simple electron transfer reaction.\nAnother theme of the talk will be the need for developing new tools to study the atomic scale dynamics occurrin g in collisions at surfaces and the progress being made in Göttingen in this regard. Some of the new methods that I will emphasize are:\n1. Scatte ring of Oriented Molecules From Surfaces\n2. Rydberg Tagging of Surface Sc attered H-Atoms\n3. Generation of Ultra-Short H-Atom Pulse Trains\n4. Impl ementation of Stark Decelerated Beams in Surface Scattering\nRELATED REFER ENCES\n1. Observation of orientation dependent electron transfer in molecu le-surface collisions\, Nils Bartels\, Kai Golibrzuch\, Christof Bartels\, Chen Li\, Daniel J. Auerbach\, Alec M. Wodtke\, Tim Schäfer*\, Proceedi ngs of the National Academy of Science\, DOI 10.1073/pnas/1312200110.\n2. Multiquantum vibrational excitation of NO scattered from Au(111): Quantita tive comparison of benchmark data to ab initio theories of nonadiabatic mo lecule-surface interactions\, Russell Cooper\, Christof Bartels\, Aleksand r Kandratsenka\, Igor Rahinov\, Niel Shenvi\, Zhisheng Li\, Daniel J. Auer bach\, John C. Tully Alec M. Wodtke\, Angew. Chemie Int. Ed.\, 124\, 5038 –5042 (2012)\n3. Inverse velocity dependence of vibrationally promoted e lectron emission from a metal surface\, Hendrik Nahler\, Jerry Larue\, Jas on White\, Daniel J. Auerbach and Alec M. Wodtke\, Science\, 321\, 1191-11 94 (2008)\n4. Conversion of large amplitude vibration to electron excitati on at a metal surface\, J. White\, J. Chen\, D. Matsiev\, D.J. Auerbach an d A.M. Wodtke\, Nature 433(7025)\,503-505\, (2005).\n5. Vibrational Promot ion of electron transfer\, Y. Huang\, S.J. Gulding\, C.T. Rettner\, D.J. A uerbach A.M. Wodtke\, Science 290\, 111-114 (2000) LOCATION:CH G1 495 https://plan.epfl.ch/?room==CH%20G1%20495 STATUS:CONFIRMED END:VEVENT END:VCALENDAR