Laser Spectroscopic Study of IonーMolecule Reactions in Photoionized Organo Molecular Clusters

1)在超音速分子束中制备的范德华络合物C_6H_5Cl-NH_3选择性电离后，有效地产生了C_6H_5NH~+_2。用双色质量选择多光子电离光谱观察了产物的作用光谱及其出现能。从反应的能量学可以看出，离子-分子反应是该反应的主要原因，产物是在光离范德华络合物中发生的亲核取代反应。2)研究了光离范德华络合物C_6H_5F与NH_3和H_2O的簇内离子-分子反应。不同异构体的选择性光致电离导致了C_6H_5F-NH_3的两种不同的簇内反应，即生成C_6H_5NH_4的取代反应和产生C_6H_5F^+的解离反应。根据实验结果和计算的异构体几何构型，讨论了反应的能量学。结果表明，亲核取代反应是C_6H_5NH~+产生的主要原因。

1) Efficient generation of C_6H_5NH^+_ was found after the selective ionization of the van der Waals complex C_6H_5C1-NH_3 which was prepared in a supersonic molecular beam. The action spectrum of the product and its appearance energy were observed by using the two-color mass-selected multiphoton ionization spectroscopy. From the energetics of the reaction it was concluded that the ion-molecule reaction is responsible for the process and the product is generated by the nucleophilic substitution reaction occurring within the photoionized van der Waals complex.2) Intracluster ion-molecule reactions of the photoionized van der Waals complexes c_6H_5F with NH_3 and with H_2O have been investigated. Two different intracluster reactions of C_6H_5F-NH_3, the substitution reaction yielding C_6H_5NH^_ and the dissociation yielding C_6H_5F^+ were induced by the selective photoionization of different isomers of the complexes. Energetics of the reactions was discussed on the bases of the experimental results and of the calculated geometries of the isomers. It was concluded that the nucleophilic substitution reaction is responsible for the C_6H_5NH^+_ production.