Wang Yanting, Teitel S, Dellago Christoph
Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627, USA.
Nano Lett. 2005 Nov;5(11):2174-8. doi: 10.1021/nl051149h.
Molecular dynamic simulations are used to study the structural stability of gold nanorods upon heating. We show that the global stability of the rod is governed by the free energetics of its surface. In particular, an instability of surface facets nucleates a bulk instability that leads to both surface and bulk reorganization of the rod. The surface reorganizes to form new, more stable, {111} facets, while the underlying fcc lattice completely reorients to align with this new surface structure. Rods with predominantly {111} facets remain stable until melting.
分子动力学模拟用于研究加热时金纳米棒的结构稳定性。我们表明，纳米棒的整体稳定性由其表面的自由能控制。特别是，表面小面的不稳定性引发了整体不稳定性，导致纳米棒的表面和整体结构重组。表面重组形成新的、更稳定的{111}小面，而底层的面心立方晶格则完全重新取向以与这种新的表面结构对齐。主要具有{111}小面的纳米棒在熔化前保持稳定。
