The quenching of NO2 fluorescence by a magnetic field

Abstract
It has been observed that the fluorescence from NO2 excited in the visible region is partially quenched by an applied magnetic field. The pressure dependence of the fluorescence intensity versus magnetic field strength curve indicates that the magnetic quenching is due to an increase in the collisional quenching cross section caused by the magnetic field. The magnetic quenching is observed to be a strong and erratic function of the exciting wavelength and this is shown to be consistent with the admixture of a nonradiating state where the amount of admixture is everywhere dominated by local perturbations. Magnetically induced changes in the absorption coefficient are also observed, and these are attributed to the tuning of energy level differences into and out of resonance with the exciting light by the magnetic field.