Extension of frozen-density embedding theory for non-variational embedded wavefunctions

Alexander Zech; Andreas Dreuw; Tomasz A Wesolowski

doi:10.1063/1.5089233

Extension of frozen-density embedding theory for non-variational embedded wavefunctions

J Chem Phys. 2019 Mar 28;150(12):121101. doi: 10.1063/1.5089233.

Authors

Alexander Zech¹, Andreas Dreuw², Tomasz A Wesolowski¹

Affiliations

¹ Department of Physical Chemistry, University of Geneva, 30, Quai Ernest-Ansermet, CH-1211 Genève 4, Switzerland.
² Interdisciplinary Center for Scientific Computing, Ruprecht-Karls University Heidelberg, Im Neuenheimer Feld 205, 69120 Heidelberg, Germany.

PMID: 30927882
DOI: 10.1063/1.5089233

Abstract

In the original formulation, frozen-density embedding theory [T. A. Wesolowski and A. Warshel, J. Phys. Chem. 97, 8050-8053 (1993); T. A. Wesołowski, Phys. Rev. A 77, 012504 (2008)] concerns multi-level simulation methods in which variational methods are used to obtain the embedded N_A-electron wavefunction. In this work, an implicit density functional for the total energy is constructed and used to derive a general expression for the total energy in methods in which the embedded N_A electrons are treated non-variationally. The formula is exact within linear expansion in density perturbations. Illustrative numerical examples are provided.