Structural transformations in amorphous selenium as studied by the differential thermal analysis and exoelectron emission technique

Abstract

The parameters (temperature, activation energy) of the surface and volume glass transition (retrification process) in amorphous selenium produced by rapid quenching of the liquid phase have been determined using the EEE and DTA techniques. EEE is a surface effect connected with structural transformations in the surface layer whereas the DTA measurements give the information about the transformations occurring in the volume of the sample. It has been found that the surface retrification of selenium occurs with activation energy smaller than the volume retrification, both observed in the first heating run. The value of activation energy for the volume retrification measured in the second DTA heating run is higher compared with that measured in the first heating run. Irradiation with X-rays accelerates both the surface and volume retrification of amorphous selenium.