SIOC English
化学学报
高级检索

化学学报 ›› 2009, Vol. 67 ›› Issue (17): 2031-2037. 上一篇    下一篇

研究论文

大气环境中的水分子团簇分布和H＋(H2O)n (n＝4～16)离子的解离

杨 鹏a 叶招莲b 蒋公羽a 李 周a
丁传凡a 侯惠奇*,b

  

  1. (a复旦大学化学系 上海 200433)
    (b复旦大学环境科学研究所 上海 200433)

  • 投稿日期:2008-12-04 修回日期:2009-03-03 发布日期:2009-09-14
  • 通讯作者: 侯惠奇

Water Cluster Distribution under Ambient Conditions and Dissociation of H＋(H2O)n (n＝4～16) Using Mass Spectrometry in Atmosphere

Yang, Penga Ye, Zhaolianb Jiang, Gongyua Li, Zhoua
Ding, Chuanfana Hou, Huiqi*,b

  

  1. (a Laser Chemistry Institute and Department of Chemistry, Fudan University, Shanghai 200433)
    (b Department of Environment, Fudan University, Shanghai 200433)
  • Received:2008-12-04 Revised:2009-03-03 Published:2009-09-14
  • Contact: Hou, Huiqi

PDF

1840

报道了用质谱学方法首次测得的大气中各种水的团簇分布情况. 表明在室内大气环境下, 水主要是以几个至几十个水分子所组成的分子团簇的形式存在, 且团簇的分布与空气湿度, 即水在空气中的分压有关. 实验中, 除观测到空气中也存在前人已报道过的具有笼状结构的H＋(H2O)21外, 还观测到其他几种较稳定结构的水的团簇, 即H＋(H2O)4, H＋(H2O)10和H＋(H2O)15. 实验中所测得的水分子团簇分布结果与使用的离子源以及质量分析器种类无关. 我们还用碰撞诱导解离(CID)的方法研究了H＋(H2O)n (n＝4～16)离子的碰撞解离产物, 结果表明, 对于H＋(H2O)n (n＝4～16)的离子, 其较稳定的离子的碰撞解离产物均为H＋(H2O)n (n＝4～6). 我们还进一步研究了H＋(H2O)10离子的碰撞解离产物与碰撞气体(即Ar气)密度的关系, 得到了碰撞气体密度与碰撞解离产物分布的关系.

关键词: 大气环境, 水分子团簇, 质谱, 碰撞解离产物

The distribution of water clusters under ambient conditions was first tested using a triple-quad-
rupole mass spectrometer coupled with a dielectric barrier discharge ionization source. The water exists as clusters rather than a single molecule under the ambient conditions, and the cluster distribution is dependent on the humility of atmosphere, or the water vapor pressure. In addition to the cluster with the magic number n＝21, H＋(H2O)n was also observed in the ambient condition, and H＋(H2O)4, H＋(H2O)10 and H＋(H2O)15 were found more stable according to the experiment. The dissociation products of H＋(H2O)n (n＝4～16) clusters were further studied with a collision induced dissociation (CID) method. The product ions were mainly H＋(H2O)n (n＝4～6). The CID products of H＋(H2O)10 with the collision gas pressure were also studied.

Key words: ambient condition, water cluster, mass spectrometry, dissociation

中图分类号: