Predictions of the mechanical and structural properties of spherical platinum nanoparticles by Chen-Mobius lattice inversion method

In this study, Chen-Mobius lattice inversion method is used to calculate the cohesive energy and bulk modulus of platinum. This method was employed to calculate the cohesive energy by summing over all pairs of atoms within platinum spherical nanoparticles. The cohesive energy was calculated by inverting the potential energy function proposed by Rose et al. (1981). The bulk modulus was derived from the cohesive energy curve as a function of particles' sizes. Both of the bulk modulus and the scaled cohesive energy decrease as the size of the nanoparticles decreases. These predictions agree qualitatively with previous measurements for some nanomaterials (γ-Al₂O₃, CdSe and PbS). For some other nanomaterials (γ-Fe₂O₃, CeO₂, Au and Ag) the bulk modulus is reported in the literature to increase as the size decreases. These inconsistent results are attributed to the higher surface to volume ratio of nanostructures (thin films, nanotubes, .etc.) compared to nanoparticles.