Size-dependent melting point of nanoparticles based on bond number calculation

An integrated model based on bond number and bond strength in a system with a cubo-octahedral structure is developed to predict the size-dependent thermal characteristics of nanoparticles. Without any adjustable parameters, this model can be used to predict the melting point and cohesive energy of low-dimensional materials, suggesting that both depend on the size and on the atomic distance. The good agreement of the theoretical prediction with the experimental and molecular dynamic simulation results confirms the validity of the cubo-octahedron in describing the thermodynamic behaviors of nanoparticles even without considering their crystalline structures.

► An united model for melting point or cohesive energy of nanoparticles is established. ► Decreased cohesive energy or melting point arises from the lowered bond number. ► Good estimation of the model is obtained even nanoparticle's structure is unknown.