The effect of size and composition on structural transitions in monometallic nanoparticles

Predicting the morphological stability of nanoparticles is an essential step towards the accurate modelling of their chemophysical properties. Here we investigate solid–solid transitions in monometallic clusters of 0.5–2.0 nm diameter at finite temperatures and we report the complex dependence of the rearrangement mechanism on the nanoparticle’s composition and size. The concerted Lipscomb’s Diamond-Square-Diamond mechanisms which connects the decahedral or the cuboctahedral to the icosahedral basins, take place only below a material dependent critical size above which surface diffusion prevails and leads to low-symmetry and defected shapes still belonging to the initial basin.