物理化学学报 >> 2008, Vol. 24 >> Issue (10): 1767-1772.doi: 10.3866/PKU.WHXB20081006

研究论文 上一篇    下一篇

二乙基锌的同步辐射真空紫外光电离光解离

杨广涛; 张国斌; 刘付轶; 杜琦; 单晓斌; 韩聚广; 盛六四   

  1. 中国科学技术大学国家同步辐射实验室, 合肥 230029
  • 收稿日期:2008-05-22 修回日期:2008-06-16 发布日期:2008-10-08
  • 通讯作者: 张国斌; 刘付轶 E-mail:gbzhang@ustc.edu.cn;fyliu@ustc.edu.cn

Synchrotron Radiation Vacuum Ultraviolet Photoionization and Photodissociation of Diethylzinc

YANG Guang-Tao; ZHANG Guo-Bin; LIU Fu-Yi; DU Qi; SHAN Xiao-Bin; HAN Ju-Guang; SHENG Liu-Si   

  1. National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, P. R. China
  • Received:2008-05-22 Revised:2008-06-16 Published:2008-10-08
  • Contact: ZHANG Guo-Bin; LIU Fu-Yi E-mail:gbzhang@ustc.edu.cn;fyliu@ustc.edu.cn

摘要: 利用同步辐射光源和反射式飞行时间质谱, 在超声冷却条件下对二乙基锌(ZnC4H10)进行真空紫外(VUV, 能量范围为8-22 eV)光电离光解离研究. 实验获得ZnC4H10的光电离质谱图; 通过测量各碎片离子的光电离效率(PIE)曲线, 获得ZnC4H10的电离势(IP=8.20±0.05 eV)及其碎片离子(ZnC2H5+、ZnH+、Zn+、C2H5+、C2H3+等)的出现势. 根据实验结果, 并结合相关文献所给的热力学数据, 推导出这些主要碎片离子的生成焓, 并分析它们可能的解离通道和主要离子的分支比. 结果表明, 其主要解离通道是母体离子发生Zn—C 键的断裂形成ZnC2H5+和C2H5+离子, ZnC2H5+离子再进一步解离形成Zn+离子, 并且含锌碎片离子的丰度占75%以上.

关键词: 二乙基锌, 同步辐射真空紫外光电离, 出现势, 电离势

Abstract: Photoionization and photodissociation of diethylzinc (ZnC4H10) were performed using vacuum ultraviolet (VUV) synchrotron radiation and a time-of-flight mass spectrometer (TOF-MS). The photoionization mass spectra of all the observed ions fromdiethylzinc and their photoionization efficiency (PIE) curves with the photon energy from8 to 22 eV were measured. From their PIE curves, the ionization potential (IP) of ZnC4H10 (IP=8.20±0.05 eV) and appearance potentials of fragment ions (ZnC2H5+, ZnH+, Zn+, C2H5+, C2H3+, etc.) were obtained. According to the gas phase energetic data from references, the formation enthalpies of chief ions were evaluated and their possible channels of dissociative photoionization as well as their branch rates were discussed. The results indicated that the chief channels were the simple cleavage of Zn—C bond in the parent ions to form fragmental ions C2H5+ and ZnC2H5+ which further dissociated to Zn+ ion. More than 75%of the total production ions belonged to Zn-containing ions.

Key words: Diethylzinc, Synchrotron radiation VUV photoionization, Appearance potential, Ionization potential

MSC2000: 

  • O643