Interest in mass spectrometry of highly oxidized dimers from α-pinene oxidation has increased in the atmospheric chemistry field. Here, we apply high-resolution collision-induced dissociation mass spectrometry (HR-CID-MS) with an atmospheric pressure ionization source to investigate in detail how α-pinene-derived dimers are detected and identified by MS. The resulting HR-CID spectra and specific fragmentation patterns suggest that a large fraction of dimer ions detected in full-scan mass spectra can be hydrogen-bonded artifact clusters and the residual small fraction includes covalently bonded actual dimers. We also show how individual fractions of the artifact clusters and actual dimers are calculated using the HR-CID spectra.

中文翻译：

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使用高分辨率碰撞诱导解离质谱法准确鉴定α-pine烯氧化生成的二聚体。

在大气化学领域中，人们越来越关注α-pine烯氧化引起的高度氧化的二聚体的质谱研究。在这里，我们将高分辨率碰撞诱导解离质谱（HR-CID-MS）与大气压电离源一起应用，以详细研究MS如何检测和鉴定α-ne烯衍生的二聚体。所得的HR-CID谱图和特定的碎片图谱表明，在全扫描质谱图中检测到的大部分二聚体离子可以是氢键合的伪影簇，而剩余的小部分包含共价键合的实际二聚体。我们还展示了如何使用HR-CID光谱计算出伪像簇和实际二聚体的各个分数。