对硝基苯乙醚的真空紫外光电离与光离解研究  

Photoionizaion and photodissociation of 1-ethoxy-4-nitrobenzene with vacuum ultraviolet synchrotron radiation

作　　者：武国华[1] 周卫东[1] 盛六四[1] 高辉[1] 刘付轶[1] 张允武[1] 

机构地区：[1]中国科学技术大学,国家同步辐射实验室,合肥230029

出　　处：《原子与分子物理学报》2000年第1期1-6,共6页Journal of Atomic and Molecular Physics

摘　　要：以同步辐射为光源,用光电离质谱和符合技术对对硝基苯乙醚分子进行了真空紫外光电离与光离解研究。测得了这一分子的电离势及C6H5NO+3、C6H5O+2、C6H5O+等六个主要碎片离子的出现势,根据实验所得的质谱图、能量关系,结合该分子的具体结构,初步分析了该分子同步辐射光离解电离的可能通道,并得到了分子离子的键离解能D0(O2NC6H4C2H+5)。In this paper, the photoionization and photodissociative ionization processes of p nitrophenetole(C 8H 9NO 3,pNPT) using coincidence technology with vacuum ultraviolet synchrotron radiation (SR) photoionizaton mass spectroscopy were reported. The ionization potential(IP) of this molecule and the appearance potentials(APs) of seven principally ionic fragments from the SR photodissociative ionization of pNPT have been measured. On the basis of the IP(pNPT) and the APs measured in this experiment, the dissociative energy D 0 (O 2NC 6H 4O C 2H + 5) has been evaluated (5.40 eV). Based on the results of the mass spectrum of pNPT obtained with SR photoionization, the possible channels of photodissociative ionization of EONB have been analyzed. There were three figures in this paper: Figure 1 was mass spectrum of pNPT obtained with vacuum ultraviolet SR photoionization, the principally peaks: m/e =167, 139,123,109,93,81,65,53,39,29 were displayed in this figure. Figure 2 was photoionization efficiency curve(PIE) of pNPT + from pNPT. From it, the ionization potential(8.76 eV) was obtained. Figure 3 shows photoionization efficiency curves of C 6H 5NO + 3,C 5H 5O +, C 2H + 5 from p nitrophenetole photoionization. In addition, two tables were shown in it. Table 1 was assignment of mass spectrum of p nitrophenetole obtained with SR photoionization, In this table, ten probably ionic drawing formula were presented. There were six appearance potentials of ionic fragments from their PIE curves respectively were given in Table 2: AP (O 2NC 6H 5O +)=10.67±0.05 eV, AP (C 6H 5O + 2)=12.84±0.10 eV, AP (C 6H 5O +)=14.22±0.10 eV, AP (C 5H 5O +)=14.07±0.10 eV, AP (C 5H 5 +)=15.05±0.10 eV, AP (C 2H 5 +)=14.16±0.10 eV. We should be aware of that the corrections due to reverse activation barriers and the kinetic shifts have been ignored. Because the reverse activation energy is often negligibly small in case where the reaction involves simple bond cleavage and the kinet

关 键 词：同步辐射 光离解 对硝基苯乙醚 真空紫外光电离 

分 类 号：O625.61[理学—有机化学]