The vibrational infrared spectrum of CoO

Abstract
The infrared spectrum of CoO has been observed in absorption by using a microwave discharge as the molecular source. The molecular constants are: υo(cm−1), 842.2(2); Be(cm−1), 0.522(5); αe×103(cm−1), 1.9. (2); re(nm), 0.160(1). The appearance of the spectrum indicates that this is a 4Σ state.