Rich collision dynamics of soft and sticky crystalline nanoparticles: numerical experiments.

A molecular dynamics study on the collisional dynamics of soft and sticky single face-centered cubic crystal nanoparticles is presented. The softness and stickiness of the nanoparticles are controlled by varying parameters in the Lennard-Jones potential that is used to describe the interatomic interactions. Softening of nanoparticles due to extensive plastic deformations is observed as was previously found in hard nanoparticles. Further, two primary plastic deformation modes, slip and twinning, of the nanoparticles are found to play important roles in the temperature dependence of the coefficient of restitution. Additionally, we observe the effects of surface roughness, facets, and edges in the collisional behaviors of the sticky nanoparticles in low-velocity collisions. Nevertheless, the Johnson-Kendall-Roberts theory for macroscopic adhesive bodies still remains valid in nearly spherical nanoparticles.