用飞行时间质谱研究激光气化法产生的气相Co/Cl团簇

Study on the Production of Gas-Phase Co/Cl Cluster by Time-of-Flight Mass Spectrometry

摘要: 本文用飞行时间质谱研究了激光气化方法产生的气相团簇离子的机理。实验发现用532um激光照射团体CoCl2·6H2O样品时，适当控制激光能量和延迟时间，可以产生大尺寸的正离子团簇CoCl＋（CoCl2）n、Co+（CoCl2）n，n=0～12，负离子团簇（CoCl2）nCl-n，＝0～5，以及溶剂化的团簇CoCl+（CoCl2）n（H2O）m，n=1～8，m＜5。通过用飞行时间质谱考察团簇的尺寸大小与激光能量，我们认为这些团簇是通过气相化学反应逐步生长的。

Abstract: Cluster ions (Cocl2 ).Co+, (CoCl2 ).CoCl+, (CoCl2 ).Cl-, (CoCl2 )', n = 1 ~ 2, andwater solvated cluster ions (CoCl2 )n. (H2O).CoCl+,n= 1~ 7,m = 1 ~5 were produced by532nm laser vaporization of CoCl. 6H2O solid pellet ithe formation mechanisms of clusters were investigated by time-of-flight mass spectrometry. We found that lager clustercan only be detected under a short range of laser energy and delay time between laserand pulsed electric accelerati0n v0ltage. All of the observed in formation indicates thatthese cluster ions are produced by a gas-phase ion-molecule reaction and aggregation ofgas phase CoCl2. Our experiment results show that large size clusteer can also be produced by direct laser vaporization of some compounds without carrying gas.