Novel detection of the C 2v isomer of carbon tetraoxide (CO 4)

Abstract

Carbon oxides such as carbon dioxide (CO 2) and carbon trioxide (CO 3) have long been known as important molecules in atmospheric and solid state chemical reactions. Although higher order carbon oxides have been theoretically predicted to be stable and also important, their detection has been difficult. Here, we report on the first spectroscopic detection of the cyclic (C 2v) isomer of carbon tetraoxide ( 12C 16O 4) via its ν 1 vibrational mode centered around 1941 cm −1 via low temperature infrared spectroscopy; the identification of the 12C 18O 4, 13C 16O 4, and 13C 18O 4, isotopologues supported by ab initio calculations confirms the assignments.