Mechanism and intensity of radical-recombination luminescence of crystal phosphors

Abstract

This paper constructs a model for radical-recombination luminescence corresponding to experimental data for the excitation of luminescence of a thulium phosphor based on zinc sulfide and calcium oxide by atomic hydrogen. The complicated dynamic behavior of a heterogeneous catalytic reaction is described by assuming that the parameters of the system vary as a function of time or by postulating that one of the stages is autocatalytic. The other method consists of rejecting unjustified assumptions and appealing to purely kinetic factors. The model in this paper incorporates all stages from the standpoint of thermodynamics. The Langmuir-Hinshelwood mechanism is employed and also modified by the assumption that the adsorbed atoms can be in two different states distinguished by different lifetimes relative to the recombination process.