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在３５５、５３２ｎｍ激光波长下用ＴＯＦ质谱研究了Ｃ４Ｈ５Ｎ－（Ｈ２Ｏ）ｎ氢键团簇体系的多光子电离。二波长下均得到一系列Ｃ４Ｈ５Ｎ-（Ｈ２Ｏ）ｎ＋及质子化产物Ｃ４Ｈ５Ｎ-（Ｈ２Ｏ）ｎＨ＋。３５５ｎｍ下可能存在双光子共振电离过程，使得该波长下吡咯母体及团簇离子信号较５３２ｎｍ有明显增强。从头计算结果表明质子化产物的质子更可能连接于吡咯环的α-Ｃ原子，而不是Ｎ原子上，即光电离过程诱发了一个簇内的质子转移反应。在５３２ｎｍ下质子化产物的生成主要来自于一个发生于团簇内部的Ｐｅｎｎｉｎｇ电离或电荷转移过程。团簇的形成对吡咯光解产物的稳定化作用使得团簇系列Ｃ４Ｈ４Ｎ-（Ｈ２Ｏ）ｎ＋出现反常强度变化。
Multiphoton ionization of C4H5N- (H2O) n hydrogen bonding cluster system was studied by TOF mass spectrometry at 355,532 nm laser wavelength. At the same wavelength, a series of C4H5N- (H2O) n + and protonated products C4H5N- (H2O) nH + were obtained. There may be a two-photon resonant ionization process at 355 nm, which makes the pyrrole precursor and cluster ion signal significantly enhanced compared with 532 nm at this wavelength. Ab initio calculations show that the protonated protons are more likely to be attached to the a-C atoms of the pyrrole ring than to the N atoms, that is, the photoionization process induces a proton transfer reaction within the cluster. The formation of protonated products at 532 nm mainly comes from a Penning ionization or charge transfer process that occurs inside the clusters. The formation of clusters on the pyrrole photolysis of the stabilizing effect makes the cluster series C4H4N- (H2O) n + abnormal intensity changes.