论文标题
使用太空老虎实验设置形成C-C6H5CN冰
Formation of c-C6H5CN ice using the SPACE TIGER experimental setup
论文作者
论文摘要
最近在星际培养基（ISM）的寒冷和致密区域中检测到苯甲腈（C-C6H5CN），在该区域中，它已被用作丰富的芳香族有机化学的路标，可能导致生产多环芳烃（PAHS）。该苯硝基菌的一种可能起源是涉及苯（C -C6H6）和硝酸分子（含有-CN组的有机分子）的星际冰化学。我们已经通过实验室实验使用了我们的新设置空间老虎，解决了该C-C6H5CN形成途径的合理性。 Space Tiger实验设置旨在使用基于激光器的冰加工和产品检测方法探索星际冰壳的物理和化学。我们发现，C-C6H5CN是在低温（4-10 K）的C-C6H6 $：C-C6H6 $：CH3CN二元冰混合物的辐射后形成的。当将C-C6H6和CH3CN嵌入CO冰基质中时，还观察到C-C6H5CN的形成，但在H2O冰基质中有效淬火。这项工作中介绍的结果表明，涉及苯和硝酸分子的星际冰化学只有当这些物种存在于冰壳顶部或嵌入在富含富含H2O的冰层中时，才有促进观察到的苯甲腈的形成。
Benzonitrile (c-C6H5CN) has been recently detected in cold and dense regions of the interstellar medium (ISM), where it has been used as a signpost of a rich aromatic organic chemistry that might lead to the production of polycyclic aromatic hydrocarbons (PAHs). One possible origin of this benzonitrile is interstellar ice chemistry involving benzene (c-C6H6) and nitrile molecules (organic molecules containing the -CN group). We have addressed the plausibility of this c-C6H5CN formation pathway through laboratory experiments using our new setup SPACE TIGER. The SPACE TIGER experimental setup is designed to explore the physics and chemistry of interstellar ice mantles using laser-based ice processing and product detection methods. We have found that c-C6H5CN is formed upon irradiation of c-C6H6$:CH3CN binary ice mixtures with 2 keV electrons and Lyman-alpha photons at low temperatures (4-10 K). Formation of c-C6H5CN was also observed when c-C6H6 and CH3CN were embedded in a CO ice matrix, but it was efficiently quenched in a H2O ice matrix. The results presented in this work imply that interstellar ice chemistry involving benzene and nitrile molecules could contribute to the formation of the observed benzonitrile only if these species are present on top of the ice mantles or embedded in the CO-rich ice layer, instead of being mixed into the H2O-rich ice layer.
