Features of explosive delayed desorption from methane-doped argon matrices

The features of delayed desorption from CH4-doped Ar matrices irradiated with an electron beam of subthreshold energy were studied. Radiolysis products were detected by emission spectroscopy. The total desorption yield was monitored by recording the pressure in the experimental chamber. It has been demonstrated that the delayed desorption is of a bulk nature. Based on the analysis of the concentration dependence of delayed desorption bursts and their structure, an assumption was made about the formation of CH4 clusters in Ar matrices. At a high dopant concentration of 10%, up to three consecutive bursts were recorded. Delayed desorption from a sample doped with 0.1% CH4 was registered for the first time. A correlation has been found between the burst of particles and the flash of luminescence of H atoms. This seemingly contradictory observation of the correlation of the H atom content with the particle explosion due to their recombination was explained by analyzing the energy transfer and capture processes and the features of the energy structure of the H2 molecule. A linear dependence of the total particle yield on the CH4 concentration in the range of 1–10% was found. The dynamics of intensity changes in the sequence of main flashes and their delay time were discussed.