High-resolution jet-cooled and room temperature infrared spectra of the ν3 CH stretch of vinoxy radical

Rotationally resolved jet-cooled and room temperature spectra of the nu(3) stretch of vinoxy radical (CH2CHO) have been obtained near 2800 cm(-1) by means of tunable infrared laser spectroscopy. About 500 transitions corresponding to b-type selection rules have been assigned in the jet-cooled spectrum recorded in the region 2809-2860 cm(-1). The band origin has been determined to be 2827.913 cm(-1). A number of lines are split into doublets by the electron spin-rotation interaction. The jet-cooled spectrum has been supplemented by transitions with high N or K values observed in the room temperature spectrum, which was recorded over the spectral region 2754-2894 cm(-1). Both local and global perturbations have been found in the upper state energy levels. Least-squares fitting of the apparently unperturbed levels yielded molecular constants as well as centrifugal distortion and spin-rotational constants for the upper state. (C) 2003 American Institute of Physics.