讲座题目：Mapping Atomic Motions with Ultrabright Electrons: Realization of the Chemists’ Gedanken Experiment
主讲人：Prof. R. J. Dwayne Miller
主持人：孙真荣教授
讲座时间：2016.11.8上午9:30
讲座地点：中北理科大楼A510室
报告人简介：
Professor R.J. Dwayne Miller is the Director of MPISD;
Professor of Chemistry and Physics, University of Toronto;
Distinguished Research Faculty Chair in Chemical and University Professor Fellow of the Royal Society of Canada,
Fellow of the Chemical Institute of Canada.
2014-present, Director, Max Planck Institute for the Structure and Dynamics of Matter
2007-present University Professor, University of Toronto
2010-2013 Director, Max Planck Group, Centre for Free Electron Laser Science/DESY
2005-2010 Director of the Institute for Optical Sciences, University of Toronto
1995-present Professor of Chemistry and Physics, University of Toronto
1992-1995 Professor of Chemistry and Optics, University of Rochester
1988-1992 Associate Professor of Chemistry and Optics, University of Rochester
1984-1988 Assistant Professor of Chemistry, University of Rochester. .
R. J. Dwayne Miller has published over 200 research articles, one book, and several reviews. 16 articles have been published in Science、Nature etc top journals and the sum of cititation is 5268, H-index is over 40. His research focus has been developing new ultrafast laser technology and spectroscopies that are aimed at providing an atomic level description of the primary events defining the structure-function of Biology. This work culminated in the development of new electron sources that provided the first view of atomic motions with sufficient time and spatial resolution to resolve the primary events involved in structural changes.
报告摘要：
One of the grand challenges in science has been to watch atomic motions during structural transitions, i.e. watch atomic motions in real time.Due to the extraordinary requirements for simultaneous spatial and temporal resolution, it was thought to be an impossible quest and has been previously discussed in the context of the purest form of a gedankenexperiment. With the recent development of ultrabright electron sources capable of literally lighting up atomic motions, this experiment has been realized (Siwick et al. Science 2003). Increased source brightness, has enabled the study of photoinduced intermolecular charge transfer process in organic systems (Gao et al Nature 2013), as well as cyclization reactions with bond formation and conserved stereochemistry used in synthetic strategies (Jean-Ruel et al JPC B 2013).One observes the innumerable possible nuclear motions collapse to a few key reaction modes.Even more dramatic reduction in complexity has been observed for the material, Me4P[Pt(dmit)2]2, which exhibits a photo-induced metal to metal electron transfer process. This study represents the first full atom resolved structural dynamics with sub-Å and 100 fs timescale resolution (Ishakawa et al Science 2015).At this resolution, without any detailed analysis, the key large-amplitude modes can be identified by eye. We now are beginning to see the underlying physics for the generalized reaction mechanisms that have been empirically discovered over time. The “magic of chemistry” is this enormous reduction in dimensionality, due to the extremely large anharmonicity in the barrier crossing region, that ultimately makes chemical concepts transferrable. How far can this reductionist view be extended with respect to complexity? In this respect, atomically resolved protein functions provide a definitive test of the collective mode coupling model (Miller Acc. Chem. Research 1994) to bridge chemistry to biology, which will be discussed as the driving force for this work.