Radiation-induced modification effects in covalent-network glass formers: Phenomenological description within unified configuration-enthalpy model

Appl Radiat Isot. 2024 Feb 24;206:111255. doi: 10.1016/j.apradiso.2024.111255. Online ahead of print.ABSTRACTExternally-induced modification activated by high-energy excitation such as γ-irradiation from 60Co source is analyzed in chalcogenide glasses in terms of radiation-structural and glass-relaxation metastability, at the example of sulphides (including stoichiometric arsenic trisulphide, As2S3) and selenides. Unified configuration-enthalpy model evolving conjugated configuration-coordinate (free energy in dependence on configuration coordinate) and thermodynamic enthalpy (temperature deviations in enthalpy, configurational entropy or free volume) diagrams is proposed to describe metastability in these glasses under external influences, such as (1) physical ageing, (2) irradiation, (3) thermal annealing, (4) rejuvenation, and their combinations. The model predicts glass stabilization in the ground state composed of partial sub-states related to (i) irradiation, (ii) rejuvenation, (iii) annealing, as well as (iv) ideal-glass deep states, connected by over-barrier jumping and through-barrier tunneling transitions. This model allows an adequate parameterization of optical responses related to metastability in these glasses defined through blue (bleaching) or red (darkening) shift in their optical transmission spectra.PMID:38422943 | DOI:10.1016/j.apradiso.2024.111255

Source: Applied Radiation and Isotopes - February 29, 2024 Category: Radiology Authors: Oleh Shpotyuk Mykola Vakiv Andriy Kovalskiy Roman Golovchak Valentina Balitska Mykhaylo Shpotyuk Source Type: research