*********************************
There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
*********************************
Title:
Hybrid Quantum Mechanics/Molecular Mechanics: Incorporating Long-Range Electrostatics through Particle-Mesh Ewald Summation
Abstract:
It is well known that solvent interactions can have a profound impact on chemical reactions. In order to capture these interactions in a quantum chemical calculation, hybrid quantum mechanics/molecular mechanics (QM/MM) methods incorporate atomistic point charge representations of the solvent atoms into the QM calculation. Conventional QM/MM methods include solvent atoms within a given radius around the QM system of interest. This truncation can introduce artifacts into the calculation, especially in systems with ions or at interfaces/heterogeneous environments.
We present a method to incorporate electrostatic interactions with the infinite bulk beyond the QM/MM cutoff distance into the QM Hamiltonian. This method (QM/MM/PME) interpolates the potential from the Particle-Mesh Ewald Summation grid employed by standard molecular dynamics packages into the exchange-correlation functional quadrature grid of a DFT calculation. We demonstrate the efficacy of the method in water and in ionic liquid. The method is implemented as an open-source python interface for Psi4 and OpenMM.
