Formation of unsaturated carbon chains through carbon chemisorption on solid CO

Masashi Tsuge; Germán Molpeceres; Ryota Ichimura; Hideko Nomura; Kenji Furuya; Naoki Watanabe

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arXiv · 2509.16978

Formation of unsaturated carbon chains through carbon chemisorption on solid CO

Masashi Tsuge·Germán Molpeceres·Ryota Ichimura·Hideko Nomura·Kenji Furuya·Naoki Watanabe

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Abstract

The interaction of carbon atoms with solid carbon monoxide (CO) is a fundamental process in astrochemistry, influencing the formation of complex organic molecules in interstellar environments. This study investigates the adsorption and reaction mechanisms of carbon atoms on solid CO under cryogenic conditions, employing a combination of experimental techniques, including photostimulated desorption and resonance-enhanced multiphoton ionization (PSD-REMPI) and infrared spectroscopy, alongside quantum chemical calculations. The results reveal the formation of oxygenated carbon chains, such as CCO, C$_3$O$_2$, and C$_5$O$_2$, as well as CO$_2$. The findings highlight the role of chemisorption and subsequent reactions in driving molecular complexity on solid CO, with implications for the chemical evolution of interstellar ices and the potential formation of prebiotic molecules.

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Masashi Tsuge, Germán Molpeceres, Ryota Ichimura, Hideko Nomura, Kenji Furuya, Naoki Watanabe. 2025-09-21. Formation of unsaturated carbon chains through carbon chemisorption on solid CO. https://arxiv.org/abs/2509.16978

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