About this Abstract |
| Meeting |
MS&T24: Materials Science & Technology
|
| Symposium
|
The American Ceramic Society Journal Awards Symposium
|
| Presentation Title |
Atomistic Origin of Structural Relaxation in Lead Metasilicate and Lithium Disilicate Glasses |
| Author(s) |
Ricardo Felipe Lancelotti, Edgar D. Zanotto, Sabyasachi Sen |
| On-Site Speaker (Planned) |
Ricardo Felipe Lancelotti |
| Abstract Scope |
Glass is a non-crystalline, thermodynamically unstable material that spontaneously relaxes towards the supercooled liquid state. While the kinetics of the relaxation process can be obtained by tracking a property variation, the experimental determination of the atomic-scale structural rearrangements by which glass relaxes remains elusive. Therefore, in this work, we investigated the medium-range order structural rearrangements occurring during relaxation in lithium disilicate and lead metasilicate glasses using Raman and Nuclear Magnetic Resonance spectroscopies. Our findings reveal that the structural relaxation of these glasses involves the Q-species disproportion reaction: Qn-1 + Qn+1 → 2Qn. This reaction tends to shift towards the right as the fictive temperature decreases. The concomitant rearrangement of the network can be consistent with the increase in the refractive index, density, and enthalpy recovery upon glass annealing, providing valuable insights into the structural changes during glass relaxation. |