Phase-Shift Studies of the Quenching of NH(c1Π) by HN3, NO, CO, and CO2

Absolute cross sections for quenching NH(c1Π) by the use of several inorganic molecules were determined at room temperature by using a phase-shift method. The NH(c1Π) radicals were produced by the photolysis of HN3 using an amplitude-modulated Xe-resonance lamp. The results obtained were as follows: 0.01(He), 12(HN3), 48(NO), 49(CO), and 30(CO2) in units of 10−16 cm2. In the case of NO, the 336 nm emission was enhanced, which suggests that NO quenches NH(c1Π) to NH(A3Π). From the phase difference between the 325 and 336 nm emissions, the quenching cross-section of NO for NH(A3Π) was estimated to be 60×10−16 cm2.