| Abstract: | By means of thermodynamic equilibrium calculations emission coefficients of molecular bands of A1O and CN are computed. For given pressure and particle concentrations the coefficients show well defined maxima at certain temperatures, usually referred to as normalized temperature of the band system. This behaviour applied to electrical arcs explains the existence of aureoles caused by molecular emission of CN and some metallic oxide bands localized at fixed distances from the centre of the arc. The local temperature of the area of maximum intensity depends not only on the dissociation energy and excitation energy of the molecule in question, but may be altered by the presence of additional components and stoichiometric conditions. Thus, the normalized temperature of band systems arising from heteronuclear molecules cannot be considered as an unchangeable quantity. |
