Hockey Emily K, Vlahos Korina, Howard Thomas, Palko Jessica, Dodson Leah G
Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States.
J Phys Chem A. 2022 May 26;126(20):3110-3123. doi: 10.1021/acs.jpca.2c00716. Epub 2022 May 18.
The matrix-isolated infrared spectrum of a hydrogen cyanide-methyl chloride complex was investigated in a solid argon matrix. HCN and CHCl were co-condensed onto a substrate held at 10 K with an excess of argon gas, and the infrared spectrum was measured using Fourier-transform infrared spectroscopy. Quantum chemical geometry optimization, harmonic frequency, and natural bonding orbital calculations indicate stabilized hydrogen- and halogen-bonded structures. The two resulting weakly bound complexes are both composed of one CHCl molecule bound to a (HCN) subunit, where the three HCN molecules are bound head-to-tail in a ring formation. Our study suggests that─in the presence of CHCl─the formation of (HCN) is promoted through complexation. Since HCN aggregates are an important precursor to prebiotic monomers (amino acids and nucleobases) and other life-bearing polymers, this study has astrophysical implications toward the search for life in space.
在固体氩基质中研究了氰化氢 - 氯甲烷络合物的基质隔离红外光谱。将HCN和CHCl与过量的氩气共冷凝到保持在10 K的基底上，并使用傅里叶变换红外光谱法测量红外光谱。量子化学几何优化、谐波频率和自然键轨道计算表明存在稳定的氢键和卤键结构。由此产生的两种弱结合络合物均由一个与（HCN）亚基结合的CHCl分子组成，其中三个HCN分子以头对尾的方式形成环状结合。我们的研究表明，在存在CHCl的情况下，通过络合作用促进了（HCN）的形成。由于HCN聚集体是益生元单体（氨基酸和核碱基）和其他含生命聚合物的重要前体，这项研究对在太空中寻找生命具有天体物理学意义。
