Scalable improvement of SPME multipolar electrostatics in anisotropic polarizable molecular mechanics using a general short-range penetration correction up to quadrupoles

摘要

We propose a general coupling of the Smooth Particle Mesh Ewald (spme) approach for distributed multipoles to a short-range charge penetration correction modifying the charge-charge, charge-dipole and charge-quadrupole energies. Such an approach significantly improves electrostatics when compared to ab initio values and has been calibrated on Symmetry-Adapted Perturbation Theory (sapt) reference data. Various neutral molecular dimers have been tested as results on charged systems (metal cation complexes) are provided. Transferability of the correction is adressed in the context of the implementation of the amoeba and sibfa polarizable force fields in the Tinker-hp software. As the choices of the multipolar distribution are discussed, conclusions are drawn for the future penetration-corrected polarizable force fields highlighting the mandatory need of non-spurious procedures for the obtention of well balanced and physically meaningful distributed moments. Finally scalability and parallelism of the short-range corrected spme approach are addressed, demonstrating that the damping function is computationally affordable and accurate for molecular dynamics simulations of complexe bio- or bioinorganic systems in periodic boundary conditions.