磷原子团簇正离子的碰撞解离研究

Collision Induced Dissociation of P_n⁺（n=4-25） with Nitrogen

摘要: 利用直接激光溅射簇源的串接飞行时间质谱计,获得了磷原子团簇正离子P_n⁺（n=4—25）与氮气的碰撞诱导离解质谱,分析了它们的碰撞解离规律,并由此对其团簇离子P_n⁺的结构特征和生长（成簇）过程进行了推测.实验表明,团簇离子主要按解离掉中性P_4m.的规律解离,基本上离解成为n'=2—8的小团簇离子,且P₄⁺和P₇⁺离子的谱峰较强.我们推测,磷原子的正离子团簇内含P₄的结构单元,其生长（成簇）过程是激光等离子体中较小的磷原子团簇正离子与正四面体的P₄分子碰撞并结合起来的。

Abstract: TOF mass spectras of collision induced dissociation of P_n⁺= 4-25) with nitrogen have been recorded on an instrument of tandem time-of-flight mass spectrometer, by direct laser ablation of red phosphorus. It was found that the main collision induced dissociation channel of cluster ions P_n⁺ is P4m’ loss and the small cluster ions（n’=2-8） are formed. The dissociative rule, structural feature, and growth process of the clusters Pn+ have been discussed.