Abstract

The photodetachment energy threshold, as well as vibrationally resolved spectral signatures of the lower lying excited states and dipole bound states in model aromatic phosphonate, sulfonate and phosphate oxyanions, has been investigated using a photofragmentation spectrometer equipped with a cold ion trap. The effect of the laser excitation was monitored by mass-selective detection of product ion fragments or, alternatively, measuring the yield of the complementary neutral radicals discriminated according to their kinetic energy. The anions phenylphosphate, phenylsulfonate and p-toluenesulfonate evidenced the expected behavior, characterized by the predominance of ionic fragmentation processes, at low energies, rapidly evolving to a scenario controlled by the electron photodetachment channel at higher energies. Surprisingly for such a similar system, the phenylphosphonate anion does not have any ionic fragmentation channels and only exhibits the presence of dipole bound states.

Graphic abstract

中文翻译：

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芳族膦酸根，磺酸根和磷酸根氧阴离子的光致碎裂和电子离解

摘要

使用配备有冷离子阱的光碎光谱仪，研究了模型芳族膦酸根，磺酸根和磷酸根氧阴离子中光解离能的阈值以及低位激发态和偶极结合态的振动分辨光谱特征。激光激发的效果通过对产物离子片段进行质量选择性检测来监控，或者通过测量根据其动能进行区分的互补中性自由基的收率来进行监控。阴离子苯基磷酸根，苯基磺酸根和对甲苯磺酸根证明了预期的行为，其特征是离子裂解过程在低能量下占主导地位，在高能量下迅速演变为受电子光解通道控制的情况。

图形摘要