Photoelectron resonance capture ionization (PERCI): a novel technique for the soft-ionization of organic compounds

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• 作者：LaFranchi ; Brian W. ; Petrucci ; Giuseppe A.
• 刊名：Journal of the American Society for Mass Spectrometry
• 出版年：2004
• 出版时间：March, 2004
• 年：2004
• 卷：15
• 期：3
• 页码：424-430
• 全文大小：198 K

文摘

Photoelectron resonance capture ionization (PERCI) is demonstrated as a sensitive ionization technique involving minimal fragmentation of organic molecules. PERCI has been used successfully to softly and efficiently ionize both strongly UV absorbing and non-absorbing molecules. Tunable low energy (<1 eV) electrons are generated by focusing a pulsed UV laser on an aluminum photocathode in the presence of gas phase analyte. Negative ions are formed through a resonance electron capture process. Mass analysis is done using a reflectron time-of-flight mass spectrometer. PERCI is demonstrated for a number of gas phase compounds and simple mixtures, including sulfur hexafluoride, nitrobenzene, nitrophenol, 2-pentanone, hexanal, heptanal, and octanal. In all cases the molecular ion (or [M − H]⁻) was observed to be the dominant peak. The 1σ limit of detection was estimated to be on the order of 10⁶ molecules in the ionization region.