嘉宾简介：
R. J. Dwayne Miller 是加拿大多伦多大学杰出教授，现就职于物理学院以及化学学院，是国际著名的物理化学家。主要从事超快物理、超快化学以及生物学、医学等领域的研究。早年于美国斯坦福大学博士毕业，入选英国皇家科学院院士以及加拿大科学院院士。在2010至2020年期间，为德国马克斯普朗克研究所汉堡分所创始人兼第一任主任。Miller教授是德国国家自然科学基金（DFG）集群项目负责人（cluster：coherent ultrafast imaging），同时，获得过加拿大国家自然科学基金以及欧盟研究基金重点项目支持（ERC advanced）等。获得过包括卢瑟福化学奖、美国化学学会 E. Bright Wilson 奖以及欧洲物理学会激光科学奖等。代表性研究成果包括：首次利用超快电子衍射实现在飞秒量级抓拍到光导金属晶格融化过程；利用啁啾激光脉冲，在视觉蛋白中首次实现量子产率的控制；利用超快多维光谱，诠释了光合作用蛋白中能量传输的机制；皮秒红外激光，实施无伤疤手术；X射线以及电子显微解析蛋白质大分子结构等。
讲座摘要：
One of the long-sought objectives in science has been to watch atomic motions on the primary timescales governing structural transitions. From a chemistry perspective, this capability would give a direct observation of reaction forces and probe the central unifying concept of transition states that links chemistry to biology. With the development of ultrabright electrons capable of literally lighting up atomic motions, this experiment has been realized (Siwick et al Science 2003) and efforts accelerated with the onset of XFELs (Miller, Science 2014). A number of different chemical reactions will be discussed from electrocyclization with conserved stereochemistry, intermolecular electron transfer for organic systems, metal to metal electron transfer, to the direct observation of a bimolecular collision and bond formation in condensed phase for the classic I3- system, in a process analogous to a molecular Newton’s cradle. These studies have discovered that these high dimensional problems, order 3N (N number of atoms in the reaction volume) representing the number of degrees of freedom in the system, distilled down to atomic projections along a few principle reaction coordinates. The specific details depend on the spatial resolution to these motions, for which <.01 Å changes in atomic position (less than the background thermal motion) has now been achieved on the 100 fs (10-13 sec) timescale. Without any detailed analysis, the key large-amplitude modes can be identified by eye from the molecular movies. This reduction in dimensionality appears to be general, arising from the very strong anharmonicity of the many body potential in the barrier crossing region. The “magic of chemistry” is this enormous reduction in dimensionality in the barrier crossing region that ultimately makes chemical concepts transferrable. How far can this reductionist view be extended with respect to complexity? The spatial-temporal correlations discovered in this work provides new insight into how chemistry scaled up to biological systems – leading to living systems.
