Mechanistic studies on the decomposition of carbon suboxide in a cometary ice analog

A cometary ice analog sample consisting primarily of carbon suboxide ice (C₃O₂) was produced from the irradiation of its precursor, carbon monoxide. This carbon suboxide sample was subjected to irradiation with energetic electrons at 10 K to simulate the interaction of carbon suboxide-rich cometary analog ices with ionizing radiation. The destruction of carbon suboxide as well as the production of the primary degradation products, dicarbon monoxide (C₂O), and carbon monoxide (CO), were monitored quantitatively by infrared spectroscopy in situ; the gas phase was simultaneously sampled via quadrupole mass spectrometry. A kinetic model was produced to help explain the decomposition kinetics of carbon suboxide in cometary ices and to infer the underlying reaction mechanisms.