Analytical Model for the Size Dependent Melting Entropy and Enthalpy of Nanomaterials

Abstract

Abstract-A simple, analytical model for the size dependent melting entropy and enthalpy is discussed by considering the cubo-octahedral structure with the change of the cluster size in the low dimension scale. Using the model, melting entropy and enthalpy of Ag, Al, Cu, Au, Ni and Pb nanomaterials are calculated as a function of cluster size. An increase in melting entropy and enthalpy of nanomaterials is observed with their size. The melting entropy and enthalpy of the nanomaterials increases as the cluster size increases because of a growing fraction of the surface atom which have large mean square displacement. This brings the entropy and enthalpy of solid nanomaterial closer to the liquid state entropy and enthalpy, and leads to decrease in melting entropy and enthalpy as nanomaterial size is reduced. A comparison between theoretical prediction with other theoretical model like as Qi's, Jiang's and Guisbiers model with the available experimental and simulation data. Reasonable agreement between the model prediction and the experimental data is found.