New models of interstellar gas–grain chemistry – I. Surface diffusion rates
New models of interstellar gas–grain chemistry – I. Surface diffusion rates
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星际气体颗粒化学的新模型 – I. 表面扩散速率
DOI：
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发表时间：
2002
期刊：
影响因子：
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通讯作者：
E. Herbst
中科院分区：
文献类型：
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作者：
D. P. Ruffle;E. Herbst
近年来，它已成为显而易见的是，从速率方程的方法和从蒙特卡罗技术获得的晶粒表面化学模型的结果之间可以存在很大的差异。这种二分法导致了改进的速率方程方法的发展，其中一个关键因素是人为减慢表面氢原子的扩散速率。最近对原子氢表面扩散速率的实验室研究表明，原子氢在晶粒上的移动速度比迄今为止所假设的要慢。这项研究似乎减少了需要修改的速率方程法。基于新的实验室工作，我们已经开发了适当的模型，气相和颗粒表面化学在静态致密云核研究的化学效应，减缓的速度，原子H可以扫描尘埃表面。此外，我们已经研究了减缓所有物种可以在晶粒表面移动的速率的影响。
In recent years it has become evident that large differences can exist between model results of grain-surface chemistry obtained from a rate equation approach and from a Monte Carlo technique. This dichotomy has led to the development of a modified rate equation method, in which a key element is the artificial slowing down of the diffusion rate of surface hydrogen atoms. Recent laboratory research into the surface diffusion rate of atomic hydrogen suggests that atomic hydrogen moves more slowly on grains than heretofore assumed. This research appears to lessen the need for modifications to the rate equation method. Based on the new laboratory work, we have developed appropriate models of gas-phase and grain-surface chemistry in quiescent dense cloud cores to examine the chemical effects of slowing down the rate at which atomic H can scan over dust surfaces. Furthermore, we have investigated the effect of slowing down the rate at which all species can move over grain surfaces.