Cluster relaxation dynamics in liquids and solids near the glass-transformation temperature
The structural relaxation in glass forming materials is studied near the glass transformation temperature Tg indicated by the heat capacity maximum. The late-time asymptote of the Kohlrausch–Williams–Watts form of the relaxation function is rationalized via the mesoscopic-scale correlated regions...
Gespeichert in:
| Datum: | 2007 |
|---|---|
| 1. Verfasser: | |
| Format: | Artikel |
| Sprache: | English |
| Veröffentlicht: |
Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України
2007
|
| Schriftenreihe: | Физика низких температур |
| Schlagworte: | |
| Online Zugang: | https://nasplib.isofts.kiev.ua/handle/123456789/121798 |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| Назва журналу: | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| Zitieren: | Cluster relaxation dynamics in liquids and solids near the glass-transformation temperature/ V.B. Kokshenev // Физика низких температур. — 2007. — Т. 33, № 6-7. — С. 805-813. — Бібліогр.: 34 назв. — англ. |
Institution
Digital Library of Periodicals of National Academy of Sciences of Ukraine| Zusammenfassung: | The structural relaxation in glass forming materials is studied near the glass transformation temperature
Tg indicated by the heat capacity maximum. The late-time asymptote of the Kohlrausch–Williams–Watts
form of the relaxation function is rationalized via the mesoscopic-scale correlated regions in terms of the
Debye-type clusters following the dynamic scaling law. It is repeatedly shown that regardless of underlying
microscopic realizations in glass formers with site disorder the structural relaxation is driven by local random
fields, described via the directed random walks model. The relaxation space dimension ds = 3 at Tg is
suggested for relaxing units of fractal dimension d f = 5/2 for quadrupolar-glass clusters in ortho–para hydrogen
mixtures, that is compared with entangled-chain clusters in polymers (d f = 1) and solid-like clusters
relaxing in supercooled molecular liquids (with ds = 6 and d f = 3). The relaxation dynamics of
orientational-glass clusters in plastic crystals is attributed to the model of continuos time random walks in
space ds = 6. As a by-product, the expansivity in polymers, molecular liquids and networks is predicted. |
|---|