Abstract:
Size-dependent melting thermodynamic quantities of metallic nanoparticles with ball shape are studied theoretically based on bond energy model. Three factors are introduced in the present model. The k factor, i.e., efficiency of space filling of crystal lattice ( the ratio between the volume of the atoms in a crystal cell and that of the crystal cell). The β factor ( the ratio between the cohesive energy of surface atom and interior atom of a crystal). The qs factor ( the packing fraction on a surface crystalline plane). With considering these factors,the melting temerature,melting entropy and melting enthalpy of free standing metallic nahoparticles with ball shape are predicated by the present model.The obtained model is also compared with the reported experimental data , molecular dynamics simulation results and the liquid drop model and the model by Qi. For the size effect on melting temperature of Au and Al nanoparticles, the results show that the present model is more close to the experimental data compared with the model by Qi. Compared with the molecular dynamics simulation results, it is show that such model can successfully predict the size-dependent melting entropy and enthalpy curves of Ag and Cu nanoparticles.
