Understanding liquids and glass transition on the basis of elastic interactions

Add to your list(s) Download to your calendar using vCal

• Dr Kostya Trachenko (University of Cambridge)
• Friday 15 May 2009, 16:00-17:00
• TCM Seminar Room, Cavendish Laboratory.

If you have a question about this talk, please contact Dr Jonathan Keeling.

Note changed time

Existing textbook expressions for the energy and heat capacity of gases and solids are widely taught in physics courses. However, no such expression exists for a liquid. Based on the old idea of Frenkel, I formulate this problem in the language of phonons, and calculate liquid energy and heat capacity for both the classical and quantum cases.

I subsequently address the old and very controversial problem of glass transition, and propose the solution that is based on elastic interactions in a liquid. Central to this discussion is the range of propagation of high-frequency elastic waves in a liquid, which I call “liquid elasticity length d”. d measures the range over which local relaxation events in a liquid elastically interact with each other via the elastic waves they induce. d is small at high temperature, and increases on lowering the temperature. This sets the cooperativity of molecular relaxation in a liquid, and gives the famous Vogel-Fulcher-Tammann law. In this picture, I also discuss other central properties of glass transition: the absence of divergence at a finite temperature, the origins of two dynamic crossovers and the origin of liquid “fragility” (Angell plot).

This talk is part of the TCM Informal Seminar Series series.

This talk is included in these lists:

• All Cavendish Laboratory Seminars
• All Talks (aka the CURE list)
• Centre for Health Leadership and Enterprise
• Combined TCM Seminars and TCM blackboard seminar listing
• Featured lists
• Hanchen DaDaDash
• Inference Group Summary
• Irregular seminars in TCM
• Lennard-Jones Centre external
• ME Seminar
• Neurons, Fake News, DNA and your iPhone: The Mathematics of Information
• PMRFPS's
• School of Physical Sciences
• TCM Seminar Room, Cavendish Laboratory
• Theory of Condensed Matter
• Thin Film Magnetic Talks
• few29

Note that ex-directory lists are not shown.