Alcohol / Water And Benzene Clusters Of Photoelectric Ionization Mass Spectrometry Study And Ab Initio Calculation,

In the past years, the cluster science has brought tremendous advances, especially that of the hydrogen-bonded clusters studies. The hydrogen bond is a weak chemical interaction that plays an important role in many areas of chemistry. Many phenomena such as solvation, energy transfer and chemical reactions are influenced by the hydrogen bond. There are large amounts of hydrogen bonds in biological molecules. And proton transfer reaction via the hydrogen bond plays an important role in life science. Investigations of hydrogen bonded clusters can provide insight into the process and mechanism of proton transfer.Along with the industry development and society s progress, the environmental pollution question is more and more serious day by day, and this brings the stern challenge for people s daily life and the health. As one of multitudinous environment pollutions, benzene can cause the enormous damage to person s body, and in recent years it obtained people s widespread research.In this paper, we present the detailed results about the studies of the multi-photon ionization of methanol-ethanol-water ternary clusters and benzene clusters, which were performed by using a molecular beam, the laser multi-photon ionization and a time-of-flight mass spectrometer as well as ab initio calculations.The mainly results of this paper are as follows:(1) The photo-ionization process of the benzene, methanol, ethanol and water mixed clusters at 355nm was studied using laser multi-photon ionization and a time-of-flight mass spectrometer. The survey obtained the methanol-ethanol-water ternary clusters, but it didn't have the benzene clusters. A series of protonated clusters (CH₃CH₂OH)_nH⁺ , (CH₃OH)(H₂O)(CH₃CH₂OH)_nH⁺, (CH₃OH)(CH₃CH₂OH)_nH⁺, (H₂O)₂(CH₃CH₂OH)_nH⁺ and (H₂O)(CH₃CH₂OH)_nH⁺ were measured. And the laser intensity and the delay time differently to the signal of cluster ions were discussed. The result suggest that the production of the protonated clusters is mainly because it has a response of proton shift after clusters ionization, and we have presented the possible proton shift channel.(2) The effect which the laser wave length, the intensity, and the delay time induced by the opening to the pulse valve have on the clusters signal were found under different experimental conditions. Moreover, we have already understood how they affect the signals through changed these conditions. We discovered that the laser energy oversized or small, the delay time opposited to the pulse valve differently to do uses in the pulse molecular beam different positions, the delay time oversized or small had disadvantage to the cluster ions production.(3) In the same experiment condition, the multi-photon ionization mass spectrums of the sample were detected at 248nm. Many cluster ions (C₆H₆)⁺ (n=1-5) were detected, but we didn't obtain mellow-water ternary clusters. The equilibrium conformations and the corresponding design parameter of (C₆H₆)⁺ ionic cluster were obtained using ab initio calculation. The main vibration frequency and the vibration image of (C₆H₆)⁺ cluster were also presented under the level of RB3LYP/6-31+G(d). The theoretical calculation gives the stable configurations of (C₆H₆)₂⁺ cluster, and the interaction energies of the stable configurations were obtained.