Glass Transition Temperature Variation as a Probe for Network Connectivity

Micoulaut, Matthieu

doi:10.1007/0-306-47113-2_10

Cited by 2 publications

(3 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We first focus on the relationship between glass‐transition temperature ( T g ) and n c . Indeed, T g has been suggested to be essentially a measure of the connectivity of the glass network 77 . As expected, we find T g increases upon increases n c (Figure 8A), which echoes the fact that higher temperatures are needed to melt glasses that are more rigid (higher n c )—since more topological constraints need to be thermally broken.…”

Section: Rigidity Diagram Of the Cas Ternary Systemsupporting

confidence: 83%

Analytical model of the network topology and rigidity of calcium aluminosilicate glasses

Yang

Zhou

et al. 2021

J. Am. Ceram. Soc.

View full text Add to dashboard Cite

Topological constraint theory (TCT) has enabled the prediction of various properties of oxide glasses as a function of their composition and structure. However, the robust application of TCT relies on accurate knowledge of the network structure and topology. Here, based on classical molecular dynamics simulations, we derive a fully analytical model describing the topology of the calcium aluminosilicate [(CaO) x (Al 2 O 3 ) y (SiO 2 ) 1−x−y , CAS] ternary system. This model yields the state of rigidity (flexible, isostatic, or stressed-rigid) of CAS systems as a function of composition and temperature. These results reveal the existence of correlations between network topology and glass-forming ability. This study suggests that glass-forming ability is encoded in the network topology of the liquid state rather than that of the glassy state.

show abstract

Section: Rigidity Diagram Of the Cas Ternary Systemsupporting

confidence: 83%

Analytical model of the network topology and rigidity of calcium aluminosilicate glasses

Yang

Zhou

et al. 2021

J. Am. Ceram. Soc.

View full text Add to dashboard Cite

show abstract

“…A large change in connectivity can be expected to result in a steeper variation of T g . While this kind of SAT application is usually quite accurate [39] in simple binary chalcogenides or even oxide glasses, it appears here that equation ( 4) is not accurate enough (broken line in figure 2) to describe the observed T g (y) variation in the present ternary glasses. There are several reasons, and we shall visit the issues in section 4.2.2.…”

Section: Stochastic Agglomeration Theory and Variations Of T G (Y) In...mentioning

confidence: 81%

“…The agglomeration processes rapidly increase as the count of LSs increases and render the calculations rather intensive. We have carried out SAT calculations [39] taking into account structural correlations between m = 0 and 1 units, between pairs of m = 1 units and between m = 0 and 2 units. From these detailed calculations, we can project the populations of the various munits, and the expected variations in T g for the two ternaries.…”

Section: Variations Of T G With Glass Compositionmentioning

confidence: 99%

Chemical alloying and light-induced collapse of intermediate phases in chalcohalide glasses

Wang

Boolchand

Jackson

et al. 2007

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

The elastic behaviour of binary Ge x Se 1−x glasses, examined in Raman scattering experiments earlier, has shown glasses at x < 0.20 to be in the flexible phase, those at x > 0.25 to be in the stressed-rigid phase and those in the 0.20 < x < 0.25 range to be in the intermediate phase (IP). The IP width in mean-coordination-number space, r = 0.10. We have now examined ternary Ge 1/4 Se 3/4−y I y glasses in Raman scattering and modulated DSC experiments, and find that the IP width dramatically collapses by an order of magnitude to r = 0.009(2). Alloying iodine for Se serves to scission the network backbone progressively as mixed Ge(Se) 4−m I m tetrahedra (m-units) emerge with 1 < m < 4. The concentrations of various m-units are quantitatively tracked in Raman scattering, and this shows the m = 1 units to be rather special because they are isostatic. The present results on Ge 1/4 Se 3/4−y I y glasses, when compared to those on Ge 1/4 S 3/4−y I y glasses, reveal crucial differences in the way the reversibility window collapse occurs. Raman scattering examined as a function of the exciting light (647 nm) power (P) in Ge 1/4 Se 3/4−y I y glasses shows the IP to systematically collapse and to vanish once P increases to 1.5 × 10 6 W cm −2 . Here, an intense beam of near-bandgap light serves to optically pump the delicate intermediate range order prevailing in the IP and reversibly destroy it.

show abstract

Glass Transition Temperature Variation as a Probe for Network Connectivity

Cited by 2 publications

References 27 publications

Analytical model of the network topology and rigidity of calcium aluminosilicate glasses

Analytical model of the network topology and rigidity of calcium aluminosilicate glasses

Chemical alloying and light-induced collapse of intermediate phases in chalcohalide glasses

Contact Info

Product

Resources

About