Matrix-Isolation Infrared Spectrum of the Free Radical CCO

Abstract

The photolysis of matrix-isolated cyanogen azide in the presence of carbon monoxide at wavelengths shorter than 2800 Å has been found to lead to the appearance of the free radical CCO in concentration sufficient for direct spectroscopic observation. This species has also been produced by the vacuum ultraviolet photolysis of matrix-isolated carbon suboxide. The three vibrational fundamentals of CCO have been observed in an argon matrix at 381, 1074, and 1978 cm−1, and CCO has been found to have a continuum near 5000 Å. Isotopic studies are consistent with a linear structure for CCO. Estimates of the force constants and thermodynamic properties are given. CCO has been observed to react with CO with little or no activation energy to form carbon suboxide. Other reactions occurring in the matrix are also discussed.