Thermal vacancies in close-packing solids
Institut für Angewandte Physik, Universität Tübingen - Auf der Morgenstelle 10, 72076 Tübingen, Germany
Received: 26 November 2013
Accepted: 24 February 2014
We derive an approximate expression for the equilibrium concentration of thermal monovacancies in solids which allows for a transparent interpretation of the vacancy volume and the energetic/entropic part in the corresponding Gibbs energy of vacancy formation . For the close-packing crystals of the hard-sphere and Lennard-Jones model systems, very good agreement with simulation data is found. Application to metals through the embedded-atom method (EAM) reveals a strong sensitivity of the variation of with temperature to details of the EAM potential. Our result allows for an approximate, but direct measurement of crystal free energies and vacancy concentration in colloidal model systems using laser tweezers.
PACS: 61.72.jd – Vacancies / 65.40.-b – Thermal properties of crystalline solids / 82.70.Dd – Colloids
© EPLA, 2014