Enthalpy relaxation in Ge–Se glassy system

Differential scanning calorimetry measurements were used to study enthalpic structural relaxation in the GeySe(100 − y) glassy system. The examined compositional range was 0 ≤ y ≤ 15. Based on the results of both, fitting and non-fitting methods, the description of relaxation behavior was obtained in terms of the Tool–Narayanaswamy–Moynihan (TNM) model. Evolution of TNM parameters with increasing germanium content was interpreted within the conception of movements of occasionally linked Se polymeric chains continuously transiting toward rather independent positional changes within heavily inter-linked segments or clusters. As such, the interpretation represents a novel approach associating a phenomenological description with factual changes in molecular structure of the material. In addition, new non-fitting method is introduced, based on the examination of the overall shape of relaxation peak and its comparison to the simulated data.