Eur. Phys. J. D 53, 63-68 (2009)
https://doi.org/10.1140/epjd/e2009-00078-8

Superheating in metal nanoparticles with non-melting surfaces

¹ MacDiarmid Institute for Advanced Materials and Nanotechnology, Industrial Research Ltd, 5040 Lower Hutt, New Zealand
² School of Chemical and Physical Sciences, Victoria University of Wellington, 6140 Wellington, New Zealand

Corresponding author: ^a s.hendy@irl.cri.nz

Received: 19 November 2008
Revised: 30 January 2009
Published online: 13 March 2009

Abstract

We construct microcanonical caloric curves for aluminium nanoparticles with non-melting surface facets and diameters of up to 11 nm using molecular dynamics simulations. We find that fcc aluminium particles can be superheated above the bulk melting temperature, but only for a finite range of particle sizes i.e. diameters between 5–9 nm. We also observe a critical particle size where solid-liquid phase coexistence becomes stable, and a second larger critical size where premelted (100) facets can coexist with solid (111) facets. Ultimately, it is the premelting of the (100) facets that appears to limit the superheating effect in these particles.