NCH Prism Plus 10.28 instal the new for windows

Using this as a guideline, we investigate different strategies for deriving a reduced set of atomic charges, dipoles, and quadrupoles capable of reproducing the reference electrostatic potential with a low error. This rank indicates the number of parameters that can be derived from the electrostatic potential in a statistically significant way. We show by tensor decomposition analyses that the molecular electrostatic potential for amino acid peptide models has an effective rank less than twice the number of atoms. Searching the Force Field Electrostatic Multipole Parameter Space. Significant errors in reproducing ab initio molecular dipole moments are found if only HD or HD-I atomic charges used.

In addition, molecular dipole moments calculated by HD, HD-I, and ChelpG atomic charges only (lmax = 0) are compared with reference ab initio values.

Both HD and HD-I atomic multipoles up to rank lmax are shown to exactly reproduce ab initio molecular multipole moments of rank L for L â‰¤ lmax. A systematic increase in precision for reproducing ab initio electrostatic properties is demonstrated by increasing the atomic multipole rank from lmax = 0 (atomic charges) to lmax = 4 (atomic hexadecapoles). In general, the HD-I atomic charges/ multipoles are found to better reproduce ab initio electrostatic properties over HD atomic charges/ multipoles. The HD and HD-I atomic charges/ multipoles are tested by comparing molecular multipole moments and the electrostatic potential (ESP) surrounding a molecule with their reference ab initio values. Atomic charges and atomic multipoles are calculated from the HD and HD-I atomic charge densities for arbitrary atomic multipole rank lmax on molecules of arbitrary shape and size. Perera, Lalith Pedersen, Lee G.Īn implementation of the Hirshfeld (HD) and Hirshfeld-Iterated (HD-I) atomic charge density partitioning schemes is described. HPAM: Hirshfeld Partitioned Atomic MultipolesĮlking, Dennis M.

NCH Prism Plus 10.28 instal the new for windows