Nureshan Dias, Alexander K. Lemmens, Anna Wannenmacher and Musahid Ahmed*,
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引用次数: 0
Abstract
We report on the photoionization of a series of small methane-water mixed clusters generated in a supersonic jet expansion. The resulting clusters are investigated by synchrotron-based single photon vacuum ultraviolet (VUV) ionization coupled with reflectron time-of-flight mass spectrometry. Pure methane clusters (CH4)n+ and protonated water clusters (WnH)+ dominate the mass spectra, however with judicious control of backing pressure and mixing ratio, mixed methane-water clusters are generated. We gain unique insights into the underlying dynamics and chemistry of methane and mixed methane-water clusters through the analysis of fragment mass spectra, and photoionization intensity curves, which provide appearance energies, which are then compared to theoretically calculated ionization energies. In particular, we provide experimental evidence of the formation of methanol upon photoionization of the mixed clusters under cold conditions, which is directly relevant to astrochemistry.
期刊介绍:
The scope of ACS Earth and Space Chemistry includes the application of analytical, experimental and theoretical chemistry to investigate research questions relevant to the Earth and Space. The journal encompasses the highly interdisciplinary nature of research in this area, while emphasizing chemistry and chemical research tools as the unifying theme. The journal publishes broadly in the domains of high- and low-temperature geochemistry, atmospheric chemistry, marine chemistry, planetary chemistry, astrochemistry, and analytical geochemistry. ACS Earth and Space Chemistry publishes Articles, Letters, Reviews, and Features to provide flexible formats to readily communicate all aspects of research in these fields.