Chemical reaction dynamics

Xueming Yang

Xueming Yang obtained his PhD degree in 1986 at the University of California, Santa Barbara. After postdoctoral work at Princeton and Berkeley, he was appointed as an associated research fellow in 1995 and became a tenured research fellow at the Institute for Atomic and Molecular Sciences in Taipei in 2000. In 2004, he moved to the State Key Laboratory of Molecular Reaction Dynamics at Dalian Institute of Chemical Physics, Chinese Academy of Sciences. He is a fellow of the American Physical Society and Royal Society of Chemistry, and also a member of the Chinese Academy of Sciences. His main research interests are in the area of dynamics of gas-phase and surface chemical reactions using advanced experimental methods.

David C. Clary

David Clary is President of Magdalen College, Oxford and is Professor of Chemistry at the University of Oxford where he directs a research group working on the theory of chemical reactions. He has held previous academic posts at Manchester, Cambridge and University College London. He has been President of the Faraday Division of the Royal Society of Chemistry and was the first Chief Scientific Adviser to the UK Foreign and Commonwealth Office. He is a Fellow of the Royal Society and was knighted in 2016 by the Queen for his services to international science.

Daniel M. Neumark

Daniel Neumark is Chancellor's Professor of Chemistry at the University of California, Berkeley. He is a physical chemist who has developed novel experiments based on negative ion photodetachment to probe transition states, cluster spectroscopy and dynamics, and free radical photodissociation. He is currently investigating time-resolved dynamics in liquid jets and attosecond dynamics in atoms, molecules, and solids. He is a Member of the National Academy of Sciences and a past recipient of the Royal Society of Chemistry Award in Chemical Dynamics.

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Chemical reactions are central in chemistry and throughout the molecular sciences. In recent years, it has become possible to understand the fundamentals of chemical reaction dynamics in great detail through advances in experimental, theoretical and computational methods. It is, therefore, very timely to have a themed issue of Chemical Society Reviews devoted to this field.

The paper by Fu, Shan, Zhang and Clary (DOI: 10.1039/C7CS00526A) describes recent advances which are allowing quantum scattering calculations to be applied to chemical reactions of polyatomic molecules. Coupled with accurate potential energy surfaces, this approach gives highly reliable predictions on the dynamics of reactions which can be compared in exquisite detail with experiments. Calculating the rate constants for chemical reactions is very useful for a range of areas including combustion, atmospheric and astrophysical chemistry. Bao and Truhlar (DOI: 10.1039/C7CS00602K) describe many recent applications of variational transition state theory, which is a general and cost-effective method for calculating reaction rates. The phenomenon of “roaming” occurs in the reactions of highly-excited molecules when minimum energy pathways are bypassed and the reaction can proceed in unexpected ways with unlikely geometries. The review by Bowman and Houston (DOI: 10.1039/C7CS00578D) describes how theory and simulation are giving novel insight into this new reaction dynamics mechanism.

The crossed molecular beam technique has given the most detailed experimental information on chemical reactions and this is the subject of the review by Pan, Liu, Caracciolo and Casavecchia (DOI: 10.1039/C7CS00601B). They describe how recent experimental advances including velocity map ion imaging techniques, rotating mass spectrometric detection with time-of-flight analysis, tunable low energy electrons and vacuum-ultraviolet synchrotron radiation are providing increased sensitivity for molecular product detection. Ion–molecule reaction dynamics is reviewed by Carrascosa, Meyer and Wester (DOI: 10.1039/C7CS00623C). They discuss how crossed-beam ion imaging techniques are giving new information on topics such as charge transfer and proton transfer in nucleophilic substitution and elimination reactions. The photodetachment of anions has emerged as a powerful technique for studying the transition states of chemical reactions. This approach is reviewed by Continetti and Guo (DOI: 10.1039/C7CS00684E), who describe how recent experimental advances in photoelectron and photoelectron–photofragment coincidence spectroscopy, together with accurate quantum mechanical calculations, have enabled the detailed study of transition state dynamics to be extended to polyatomic systems.

Criegee intermediates are carbonyl oxides with two charge centres and are thought to play important roles in atmospheric chemistry. The review by Lin and Chao (DOI: 10.1039/C7CS00336F) describes a new synthesis route which produces Criegee intermediates at a high concentration which allows for their direct detection through a variety of spectroscopic methods. Although much of the research on reaction dynamics has been on gas phase processes, some researchers are now turning to reactions in liquids. This is the subject of the review by Orr-Ewing (DOI: 10.1039/C7CS00331E), who describes the different ways in which a solvent affects chemical reactions. Both experimental and computational studies are described and the important implications for research in other fields such as mechanistic synthetic chemistry are discussed.

The reviews in this themed issue on Chemical Reaction Dynamics give a snapshot of how new experimental and theoretical research in the second decade of the 21st century is advancing our understanding of chemical reactions and is having important application to a broad variety of current scientific questions.

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