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论文类型：期刊论文
发表时间：2008-07-01
发表刊物：RAPID COMMUNICATIONS IN MASS SPECTROMETRY
收录刊物：SCIE
卷号：22
期号：13
页面范围：2109-2114
ISSN号：0951-4198
摘要：Electron impact mass spectra of four long-chain isocyanates, lauryl isocyanate, tetradecyl isocyanate, hexadecyl isocyanate and octadecyl isocyanate, were obtained with a GCT high-resolution time-of-flight mass spectrometer. The four isocyanates studied gave a common base peak of m/z 99, which suggested the formation of a stable six-membered ring structure to decentralize the positive charge. Quantum-mechanical energy calculation justified that the six-membered ring base peak had the lowest energy. The positive charge assigned during the fragmentation of the radical cation, and the relative intensity of the fragment ion peaks, were explained by quantum-mechanical calculations as well. Copyright (C) 2008 John Wiley & Sons, Ltd.