氟磺酸和氯磺酸：OH伸缩倍频诱导光解离的可能候选物。

Fluorosulfonic acid and chlorosulfonic acid: possible candidates for OH-stretching overtone-induced photodissociation.

作者信息

Lane Joseph R, Kjaergaard Henrik G

机构信息

Department of Chemistry, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand.

出版信息

J Phys Chem A. 2007 Oct 4;111(39):9707-13. doi: 10.1021/jp074436d. Epub 2007 Sep 1.

DOI:10.1021/jp074436d

PMID:17764162

Abstract

We have calculated the stationary points and internal reaction coordinate pathway for the dissociation of fluorosulfonic acid (FSO3H) and chlorosulfonic acid (ClSO3H). These sulfonic acids dissociate to sulfur trioxide and hydrogen fluoride and chloride, respectively. We have calculated the frequencies and intensities of the OH-stretching transitions of FSO3H and ClSO3H with an anharmonic oscillator local mode model. We find that excitation of the fourth and third OH-stretching overtones provide adequate energy for photodissociation of FSO3H and ClSO3H, respectively. We propose that experimental detection of the products of OH-stretching overtone-induced photodissociation of FSO3H and ClSO3H would be easier than the sulfuric acid (H2SO4) equivalent. The photodissociation of H2SO4 is thought to be important in the stratosphere. The FSO3H and ClSO3H experiment could be used in proxy to support the recently proposed OH-stretching overtone-induced photodissociation mechanism of H2SO4.

摘要

我们已经计算了氟磺酸（FSO₃H）和氯磺酸（ClSO₃H）解离的驻点和内反应坐标路径。这些磺酸分别解离为三氧化硫和氟化氢以及氯化氢。我们使用非谐振子局域模模型计算了FSO₃H和ClSO₃H的OH伸缩跃迁的频率和强度。我们发现，分别激发FSO₃H和ClSO₃H的第四和第三OH伸缩泛音能为它们的光解离提供足够的能量。我们提出，对FSO₃H和ClSO₃H的OH伸缩泛音诱导光解离产物进行实验检测，要比检测硫酸（H₂SO₄）的等效产物更容易。硫酸的光解离在平流层中被认为是很重要的。FSO₃H和ClSO₃H实验可以用来间接支持最近提出的硫酸的OH伸缩泛音诱导光解离机制。