Relaxation and Fragility in Chalcogenide Network Glasses

Department of Materials Science and Engineering, University of Arizona, 4715 E. Ft Lowell Road, Tucson, AZ85712, USA pierre u.arizona.edu 

Chalcogenide glasses are largely recognized for their wide transparency in the infrared domain, which makes them the 

It can be shown that these effects are similarly linked to network coordination and fragility [22, 40], 

Chalcogenide glasses are therefore very rich systems for studying relaxation processes. This chapter intends to review and discuss the connection between these various structural relaxation phenomena and the concepts of fragility and network coordination. 

Several other physical properties besides mechanical properties also exhibit optimal behavior near r = 2.4. These properties range from density and thermal expansion to glass-forming ability [11, 16, 44]. For example. Fig. 2.2 shows the density and liquid thermal expansion versus r for the binary Ge-Se and ternary Ge-Sb-Se systems. Both properties show clear extrema near r = 2.4. 

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