Excitation and quenching of ultraviolet nitrogen bands in the mixture of N 2 and O 2 molecules

Abstract

Total quenching rate coefficients of three singlet and three triplet states of molecular nitrogen in the collisions with O 2 molecules are calculated on the basis of quantum-chemical approximations. The calculated rate coefficients of electronic quenching of N 2 ⁎ molecules are compared with the available experimental data. An influence of collisional processes on vibrational populations of electronically excited N 2( a 1Π g ) and N 2(A 3Σ u +) molecules is studied for conditions of laboratory discharge in N 2 and O 2 at admixtures of molecular oxygen 0%–20% for the pressures 1–1000 Pa. It is indicated that molecular collisions cause changes in relative populations of vibrational levels of these states and intensity relations of ultraviolet bands of N 2 with rise in the pressure and the O 2 admixture.