The high resolution infrared spectroscopy of cyanogen di-N-oxide (ONCCNO)

Abstract

The high-resolution infrared absorption spectrum of the oxalodinitrile di-N-oxide (ONCCNO) molecule has been recorded in the gas phase with a Fourier transform spectrometer at a resolution of 0.003 cm−1. No previous high-resolution spectra have been recorded for this semistable palindromic molecule. On the basis of the 2:1 intensity alternation in the rotational lines caused by nitrogen nuclear spin statistics, the ONCCNO molecule appears to be linear. A quasilinear structure, however, cannot be ruled out at this stage of the analysis. The ν4 and ν5 fundamental modes at 2246.040 55(23) cm−1 and 1258.475 30(11) cm−1 have been analyzed to give ground state rotational constants of B0=0.042 202 10(96) cm−1 and D0=8.77(70)×10−10 cm−1. By fixing the CN and NO bond lengths to 1.1923 and 1.1730 Å, respectively, the C–C bond length was determined to be 1.3329 Å using the B0 value. This short C–C bond length is thus similar to that observed for a carbon–carbon double bond.