Energy-conserving, Linear-scaling Quantum Molecular Dynamics

Marc J. Cawkwell, Anders M. N. Niklasson, T-1 Molecular dynamics (MD) simulations are used heavily in materials science, chemistry, and biology to study the evolution of structures, defects, and non-equilibrium phenomena at the atomic scale. In an MD simulation atoms move over a number of finite time steps according to the force acting on them. These forces are computed from the interatomic potential that gives the potential energy of the system as a function of the relative positions of all of the atoms. The ability of a simulation to capture the system of interest with high fidelity is determined almost entirely by the physical accuracy of the interatomic potential. It is well established that explicitly quantum mechanical models provide the most accurate descriptions of bonding, but it is not possible to employ these methods in large-scale simulations owing to their prohibitive computational cost.