Multiscale Simulation of Organic Electronics Via Smart Scheduling of Quantum Mechanics Computations

Simulation of charge transport in disordered organic materials requires a huge number of quantum mechanical calculations and becomes particularly challenging when the polaron effect is explicitly included, i.e. the influence of the electrostatic environment of the molecules on the energy disorder. The polaron model gives rise to tasks of varying resource footprints and to dependencies between a large number of tasks. We solve the resulting tightly coupled multiscale model using the quantum patch approach by accounting for the dependencies arising from the self-consistency loops for constructing the workflow and applying a specific scheduling strategy for different task types. Our implementation of the method fully exploits the parallelism of the multiscale model alleviating the effects of load imbalance and dependencies so that it can be efficiently used on high performance computing machines.