Large-Scale FMO-MP2 Calculations of the Spike Protein Droplet Model

The spike protein of SARS-CoV-2 is a challenging target for theoretical approaches. Here we report a benchmark calculation of the spike protein droplet model by the fragment molecular orbital (FMO) at the second-order Møller-Plesset perturbation (MP2) level on the supercomputer Fugaku. One hundred structure samples from molecular dynamics (MD) simulations were used for both the closed and open forms of this protein (PDB IDs 6XLU and 6XM0 respectively). The number of total fragments is about 20,000, and the job time per structure was about 2 h on 8 racks of Fugaku.