Re-investigation of the (3, 0) band in the b4Σ− - a4Π system for nitric oxide by laser absorption spectroscopy.

Nitric oxide (NO) radicals in the a 4 Π state were produced by discharging the mixture of NO gas and helium at the audio frequency. In the near infrared region, the spectra of the b 4 Σ − - a 4 Π system of the NO radical were studied by optical heterodyne - concentration modulation laser absorption spectroscopy. More than one hundred and thirty lines and eleven branches were recorded for the first time and assigned to the (3, 0) band. A global fitting was carried out to extract the molecular constants. In particular, the parameters D , p , γ and A D were precisely determined. [ABSTRACT FROM AUTHOR]