Crystals for 60-, 256- and 320-atom binary Lennard-Jones mixtures

Binary Lennard-Jones mixtures are very popular in the simulation of glassy materials. The global minima presented here are for an 80-20 mixture, as first used by Kob and Anderson¹, with parameters sigma(AA) = 1.0, sigma(AB) = 0.8, sigma(BB) = 0.88, epsilon(AA)=1.00, epsilon(AB) = 1.5 and epsilon(BB) = 0.5. The units of energy and length are epsilon(AA) and sigma(AA), respectively, and the number density is 1.2. We present the energies calculated using two different shifting techniques: Kob-Anderson (KA)¹, which simply uses a constant to make the potential continuous at the cutoff; and Stoddard-Ford (SF)² which uses a quadratic function so that the first derivatives are also continuous. We present results for a cutoff of 2.5 times the appropriate value of sigma for the both shifting techniques. For the SF technique we also include results for a cutoff of 1.842.

The systems presented here are not clusters, as they have periodic boundary conditions. The x,y, and z box lengths are contained in the first line of the xyz points files. The gifs for the 60- and 320-atom systems depict the 20- and 10- atom unit cells for these systems, respectively.