Density extrapolation in conformational domains using a reference density matrix and explicit overlap matrix dependence

Abstract

Using the density matrix extrapolation method based on the Löwdin Transform, the process of obtaining a density matrix at some intermediate conformation from several density matrices at surrounding conformations can be reversed. Based on a single reference density matrix within a conformational domain, for example, a catchment region, one may obtain approximate densities for any conformation throughout the domain, based on a simple matrix equation depending explicitly on the easily computable overlap matrices at various conformations. The approach is an extension of the earlier density matrix extrapolation method along reaction paths and the polyhedral deformation method of functional group distributions in large molecules. The extrapolation approach is motivated by the Holographic Electron Density Theorem as applied for latent property prediction. The new method is suggested for an efficient mapping of regions of potential energy hypersurfaces of both small and large molecules, where the reference density matrix for latter is obtained by the linear-scaling ADMA (Adjustable Density Matrix Assembler) method