The temperature-dependence of rapid low temperature reactions: experiment, understanding and prediction.
The temperature-dependence of rapid low temperature reactions: experiment, understanding and prediction.
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快速低温反应的温度依赖性：实验、理解和预测。
DOI：
10.1039/b600721j
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发表时间：
2006
影响因子：
3.4
通讯作者：
D. Quan
中科院分区：
文献类型：
--
作者：
Ian W. M. Smith;A. Sage;N. Donahue;E. Herbst;D. Quan
尽管CRESU（Cinétique de Réaction en Ecoulement Supersonique Uniforme）方法成功地测量了接近稠密星际云中普遍存在的极低温度的自由基中性-中性反应的速率系数，但在这些物体的化学中，仍有许多具有潜在重要性的反应尚未测量低温速率系数。一类重要的反应是原子和分子自由基与不饱和烃，即炔和烯之间的反应。基于半经验的论点和“室温”速率系数k（298 K）的相关性，对于这类反应，炔/烯的电离能与自由基的电子亲合能之间的差异，我们提出了自由基C（3 P），O（3 P），N（4S），CH，C2 H和CN之间的反应，碳链分子（Cn）和氰基多炔（HC 2nCN和NCC 2nCN）在致密ISC的温度下可能是快速的。这些反应和速率系数已被纳入一个纯气相模型（osu 2005）的ISC化学。这些计算的结果，并进行了讨论。
Despite the success of the CRESU (Cinétique de Réaction en Ecoulement Supersonique Uniforme) method in measuring rate coefficients for neutral-neutral reactions of radicals down close to the very low temperatures prevalent in dense interstellar clouds (ISCs), there are still many reactions of potential importance in the chemistry of these objects for which there have been no measurements of low temperature rate coefficients. One important class of reactions is that between atomic and molecular free radicals and unsaturated hydrocarbons; that is, alkynes and alkenes. Based on semi-empirical arguments and correlations of 'room temperature' rate coefficients, k(298 K), for reactions of this type with the difference between the ionisation energy of the alkyne/alkene and the electron affinity of the radical, we suggest which reactions between the radicals, C(3P), O(3P), N(4S), CH, C2H and CN, and carbon chain molecules (Cn) and cyanopolyynes (HC2nCN and NCC2nCN) are likely to be fast at the temperature of dense ISCs. These reactions and rate coefficients have been incorporated into a purely gas-phase model (osu2005) of ISC chemistry. The results of these calculations are presented and discussed.