Cooperative rearranging region size and free volume in As-Se glasses.

J Phys Condens Matter

Laboratoire PBM, UMR 6522, LECAP, Institut des Matériaux de Rouen, Université de Rouen, Faculté des Sciences, Avenue de l'Université BP 12, 76801 Saint Etienne du Rouvray, France.

Published: February 2009

Glasses of the As-Se system have been used as model objects of the covalent disordered inorganic polymers to investigate the correlation between the cooperative rearranging region (CRR) size determined at the glass transition temperature and the free volume fraction in the glassy state. The CRR size has been determined using temperature modulated differential scanning calorimetry data according to Donth's approach, while the free volume fraction in the investigated materials has been estimated using positron annihilation lifetime spectroscopy data. The obtained results testify that the appearance of open-volume defects greater than 80 Å(3) leads to a significant decrease in the CRR size.

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http://dx.doi.org/10.1088/0953-8984/21/7/075105DOI Listing

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