Copper oxide cluster ions CunOm n=1-22, m=1-12 are generated by 523 nm laser ablation of CuCO3 solid sample with Time of Flight Mass Spectrometer detection.By changing precursor, we get sbolar TOF MS from Cu(NO3)2 sample, but narrower mass distribution from CuO sample. We suggest that this is caused by collisionally stabilization. Small gas molecules CO2 and NO2, generated by laser ablation of CuCO3 and Cu(NO3)2, act as bther gas in supersonic molecular bearns, and they are helpful for the production of high mass clusters.
团簇是由原子或分子组成的聚合体,它们的成键包括从弱的van der Waals力、氢键到强的离子键、金属键、共价键和配位键。在原子、分子向凝聚态转变过程中,团簇的形成和增长起着核心的作用。通常利用分子束和激光气化固体样品等动力学方法可以产生各种团簇。尽管实验上可以控制产生各种团簇,但是许多团簇通常不是热力学上稳定的物种并且极易发生解离和增长反应,这样形成的一系列团簇不仅是瞬态存在的而且浓度也低,因此化学上分离团簇是比较困难的;虽然团簇的组成利用质谱方法容易指认。