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arXiv · 2305.11409

Catalytic role of HI in the interstellar synthesis of complex organic molecule

Shuming Yang·Peng Xie·Enwei Liang·Zhao Wang
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Abstract

Using quantum chemical calculations, we model the pathways for synthesizing two purine nucleobases, adenine and guanine, in the gas-phase interstellar environment, surrounded by neutral atomic hydrogen (HI). HI is found active in facilitating a series of fundamental proton transfer processes of organic synthesis, including bond formation, cyclization, dehydrogenation, and H migration. The reactive potential barriers were significantly reduced in the alternative pathways created by HI, leading to a remarkable increase in the reaction rate. The presence of HI also lowered the reactive activation temperature from 757.8 K to 131.5-147.0 K, indicating the thermodynamic feasibility of these pathways in star-forming regions where some of the reactants have been astronomically detected. Our findings suggest that HI may serve as an effective catalyst for interstellar organic synthesis.

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Shuming Yang, Peng Xie, Enwei Liang, Zhao Wang. 2023-05-19. Catalytic role of HI in the interstellar synthesis of complex organic molecule. https://doi.org/10.1088/1674-4527/accb25

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