Interaction Potential for Faceted Nanoparticles.

There is a growing interest in studying the assembly of faceted nanocrystals due to the potential of such anisotropic particles to yield unconventional structures with unique electrical, optical, and mechanical properties. While the van der Waals (vdW) interactions between spherical particles can be well-described by analytical functions, no such closed-form expressions are available to describe the vdW interactions between faceted particles. This is especially problematic in molecular simulations of particle assembly, where exact descriptions of interparticle energies in terms of interatomic interactions become computationally prohibitive, requiring a polynomial time algorithm. In this work, we formulate analytical expressions for vdW interactions between faceted particle by taking advantage of available expressions for macroscopic body interactions and by converting the energy integration over the particles’ bodies to integration over the particles’ facets. We show that the expressions provide reasonably accurate descriptions of the position and orientation dependence of vdW interactions. Since this method is a constant time algorithm, O(1), it could improve the computational efficiency of simulating faceted particles by several orders of magnitude.