Hybrid HPC and Quantum Computing Framework for Multiscale Modeling of Chemical Systems.

We present a multiscale workflow for coupling quantum computing algorithms for quantum chemical calculations with conventional high-performance computing (HPC) software. The resulting embedding framework, implemented in the multiscale computational chemistry environment ChemShell, combines a generic N-layer subtractive quantum mechanics/molecular mechanics (QM/MM) scheme and selection of an active orbital space for the quantum algorithm region. We have benchmarked the embedding models for gas phase and solvated molecules to understand the performance, benefits and current limitations of embedding quantum computing algorithms within a QM/MM model. We compare the performance of simulated quantum phase estimation (QPE) calculations on an HPC cluster using graphical processing units (GPUs) and central processing units (CPUs).