您当前所在位置: 首页 > 学者

郑旭明

  • 33浏览

  • 0点赞

  • 0收藏

  • 0分享

  • 75下载

  • 0评论

  • 引用

期刊论文

Photoisomerization reaction of CH2BrI following A-band and B-band photoexcitation in the solution phase: Transient resonance Raman observation of the iso-CH2I–Br photoproduct

郑旭明Xuming Zheng. and David Lee Phillipsa)

J. Chem. Phys., Vol. 113, No.8, 22 August 2000,-0001,():

URL:

摘要/描述

We present nanosecond transient resonance Raman experiments that investigate the photoproduct species formed following A-band and B-band excitation of bromoiodomethane in room temperature cyclohexane solutions. Density functional theory calculations were also performed for several species that have been proposed as photoproducts for photodissociation of bromoiodomethane in the condensed phase. Comparison of the experimental resonance Raman spectra to density functional theory computational results and results for the closely related iso-CH2I-I and iso-CH2Br-Br species demonstrated that the iso-CH2I–Br species is mainly responsible for a transient absorption spectrum that appears after either A-band or B-band photoexcitation of bromoiodomethane in cyclohexane solution. This is in contrast to previous results for low temperature (12 K) solids where mainly the iso-CH2Br-I species was observed following A-band photoexcitation of bromoiodomethane. Further density functional theory computational results indicate that the iso CH2I–Br species is noticeably more stable than the iso-CH2Br-I species by about 4.1kcal/mol. This suggests that although both iso-CH2I–Br and iso-CH2Br–I species may be initially produced following ultraviolet excitation of bromoiodomethane in cyclohexane solution, only the more stable isomer has a sufficiently long lifetime to be observed in our nanosecond time-scale transient resonance Raman experiments. We compare results for the bromoiodomethane ultraviolet photodissociation/photoisomerization reactions in the condensed phase to those of the closely related diiodomethane system and discuss a probable mechanism for the formation of the iso-bromoiodomethane species in the condensed phase.

关键词:

【免责声明】以下全部内容由[郑旭明]上传于[2005年04月18日 22时42分48秒],版权归原创者所有。本文仅代表作者本人观点,与本网站无关。本网站对文中陈述、观点判断保持中立,不对所包含内容的准确性、可靠性或完整性提供任何明示或暗示的保证。请读者仅作参考,并请自行承担全部责任。

我要评论

全部评论 0

本学者其他成果

    同领域成果