Smith Ian W M
Department of Chemistry, The University of Birmingham, Edgbaston, UK.
Angew Chem Int Ed Engl. 2006 Apr 28;45(18):2842-61. doi: 10.1002/anie.200502747.
Advances in experimental techniques, especially the development of the CRESU (Cinétique de Réaction en Ecoulement Supersonique Uniforme) method, allow many gas-phase molecular processes to be studied at very low temperatures. This Review focuses on the reactions of molecular and atomic radicals with neutral molecules. Rate constants for almost 50 such reactions have been measured at temperatures as low as 13 K by using the CRESU method. The surprising demonstration that so many reactions between electrically neutral species can be extremely rapid at these very low temperatures has excited interest both from theoreticians and from those seeking to understand the chemistry that gives rise to the 135 or so molecules that are present in low-temperature molecular clouds in the interstellar medium. Theoretical treatments of these reactions are based on the idea that a reaction occurs when the long-range potential between the reagent species brings them into close contact. The astrochemical context, theoretical studies, and the determination of the rate constants of these low-temperature reactions are critically discussed.
实验技术的进步，尤其是超音速均匀流动反应动力学（CRESU）方法的发展，使得许多气相分子过程能够在极低温度下进行研究。本综述聚焦于分子自由基和原子自由基与中性分子的反应。通过使用CRESU方法，已在低至13 K的温度下测量了近50个此类反应的速率常数。如此多中性物种之间的反应在这些极低温度下能极其迅速地发生，这一惊人的发现激发了理论学家以及那些试图理解星际介质中低温分子云里约135种分子形成过程的化学家们的兴趣。这些反应的理论处理基于这样一种观点，即当反应物物种之间的长程势使它们紧密接触时，反应就会发生。本文将对这些低温反应的天体化学背景、理论研究以及速率常数的测定进行批判性讨论。
