abstract
The current study reports on the relaxation behaviour of lithium silicate based glasses as probed by NMR spectroscopy. A total of four glass compositions were studied with the parent composition being 28Li(2)O-72SiO(2), and added dopants of Al and B. All the compositions showed significant differences in the NMR spectra of both annealed and non-annealed glasses demonstrating the structural relaxation behaviour. We extended our binary statistical mechanical model to these complex compositions to study the relaxation behaviour. By the combined use of the extended statistical mechanical model and broken ergodicity, we shed light on the mechanism of structural relaxation as understood by NMR spectroscopy. We studied the crystallization behaviour of the glasses and reported on the variations of the residual glass composition changes in the crystallization fraction.
keywords
SOLID-STATE NMR; HIGH-RESOLUTION AL-27; BOROSILICATE GLASSES; MAS-NMR; INORGANIC GLASSES; BORATE GLASSES; ALUMINOSILICATE GLASSES; RAMAN-SPECTROSCOPY; PHOSPHATE-GLASSES; LI2O-SIO2 SYSTEM
subject category
Chemistry; Physics
authors
Gaddam, A; Fernandes, HR; Doumert, B; Montagne, L; Ferreira, JMF
our authors
Anuraag Gaddam
Assistant Researcher
Hugo Alexandre Gonçalves da Rocha Fernandes
Junior Researcher
José Maria da Fonte Ferreira
Retired ProfessorGroups
G1 - Porous Materials and Nanosystems
G3 - Electrochemical Materials, Interfaces and Coatings
G5 - Biomimetic, Biological and Living Materials
acknowledgements
This work was funded by the JECS trust (Contract 201478) and Anuraag Gaddam is thankful for the stay in Lille; and developed within the scope of the project CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020. Hugo R. Fernandes is grateful for the Post-Doctoral Grant (SFRH/BPD/110883/2015) from the Fundacao para a Ciencia e a Tecnologia (FCT), Portugal. Lionel Montagne thanks the Chevreul Institute (FR 2638) for providing access to NMR measurements. Chevreul Institute is supported by the "Ministere de l'Enseignement Superieur et de la Recherche'', the "Region Nord-Pas de calais'' and the "Fonds Europeen de Developpement des Regions''.