title: Ewald mesh method for quantum mechanical calculations.
abstract: The Fourier transform Coulomb (FTC) method has been shown to be effective for the fast and accurate calculation of long-range Coulomb interactions between diffuse (low-energy cutoff) densities in quantum mechanical (QM) systems. In this work, we split the potential of a compact (high-energy cutoff) density into short-range and long-range components, similarly to how point charges are handled in the Ewald mesh methods in molecular mechanics simulations. With this linear scaling QM Ewald mesh method, the long-range potential of compact densities can be represented on the same grid as the diffuse densities that are treated by the FTC method. The new method is accurate and significantly reduces the amount of computational time on short-range interactions, especially when it is compared to the continuous fast multipole method.
authors.affiliation: Q-Chem Inc., 5001 Baum Blvd, Suite 690, Pittsburgh, Pennsylvania 15213, USA. chunmins@gmail.com
authors.forename: Chun-Min
authors.initials: CM
authors.lastname: Chang
authors.forename: Yihan
authors.initials: Y
authors.lastname: Shao
authors.forename: Jing
authors.initials: J
authors.lastname: Kong
mesh_terms: D004058:Diffusion; D011789:Quantum Theory