Local Potential Functional Embedding Theory of Molecular Systems: Localized Orbital-Based Embedding from an Exact Density-Functional Perspective

Abstract

Localized orbital-based quantum embedding, as originally formulated in the context of density matrix embedding theory (DMET), is revisited from the perspective of lattice density functional theory (DFT). An in-principle exact (in the sense of full configuration interaction) formulation of the theory, where the occupations of the localized orbitals play the role of the density, is derived for any (model or ab initio) electronic Hamiltonian. From this general formalism we deduce an exact relation between the local Hartree-exchange-correlation (Hxc) potential of the full-size Kohn-Sham (KS) lattice-like system and the embedding chemical potential that is adjusted on each embedded fragment, individually, such that both KS and embedding cluster systems reproduce the exact same local density. When well-identified density-functional approximations (that find their justification in the strongly correlated regime) are applied, a practical self-consistent local potential functional embedding theory (LPFET), where the local Hxc potential becomes the basic variable, naturally emerges from the theory. LPFET differs from previous density embedding approaches by its fragment-dependent embedding chemical potential expression, which is a simple functional of the Hxc potential. Numerical calculations on prototypical systems show the ability of such an ansatz to improve substantially the description of density profiles (localized orbitals occupation numbers in this context) in strongly correlated systems.

References in corpus (33)

• Quantum embedding theories
• Systematic electronic structure in the cuprate parent state from quantum many-body simulations
• Toward Practical Quantum Embedding Simulation of Realistic Chemical Systems on Near-term Quantum Computers
• Systematic improvability in quantum embedding for real materials
• On the exact formulation of multi-configuration density-functional theory: electron density versus orbitals occupation
• Ensemble Density Functional Theory of Neutral and Charged Excitations
• Dynamical Mean Field Theory, Density-Matrix Embedding Theory and Rotationally Invariant Slave Bosons: a Unified Perspective
• Cluster size convergence of the density matrix embedding theory and its dynamical cluster formulation: a study with an auxiliary-field quantum Monte Carlo solver
• Cluster Density Matrix Embedding Theory for Quantum Spin Systems
• Energy-weighted density matrix embedding of open correlated chemical fragments
• Rotationally invariant slave-boson and density matrix embedding theory: A unified framework and a comparative study on the 1D and 2D Hubbard Model
• Ab initio Quantum Simulation of Strongly Correlated Materials with Quantum Embedding
• Fully Algebraic and Self-consistent Effective Dynamics in a Static Quantum Embedding
• Rigorous screened interactions for realistic correlated electron systems
• On the effective reconstruction of expectation values from ab initio quantum embedding
• Householder transformed density matrix functional embedding theory
• Extending Density Matrix Embedding: A Static Two-Particle Theory
• Ab initio quantum many-body description of superconducting trends in the cuprates
• Multiscale Embedding for Quantum Computing
• Uniqueness of density-to-potential mapping for fermionic lattice systems
• Multi-site Reaction Dynamics Through Multi-fragment Density Matrix Embedding
• Interacting-bath dynamical embedding for capturing non-local electron correlation in solids
• Quantum embedding of multi-orbital fragments using the Block-Householder-transformation
• Local Potential Functional Embedding Theory: A Self-Consistent Flavor of Density Functional Theory for Lattices without Density Functionals
• High ground state overlap via quantum embedding methods
• A unified density-matrix functional construction of quantum baths in density matrix embedding theory beyond the mean-field approximation
• Derivation of the Ghost Gutzwiller Approximation from Quantum Embedding principles: the Ghost Density Matrix Embedding Theory
• Quantum embedding for molecules using auxiliary particles -- The ghost Gutzwiller Ansatz
• Geometrical Perspective on Spin-Lattice Density-Functional Theory
• Geometry of Degeneracy in Potential and Density Space
• FragPT2: Multi-Fragment Wavefunction Embedding with Perturbative Interactions
• Unitary transformations within density matrix embedding approaches: A novel perspective on the self-consistent scheme for electronic structure calculation
• Fragment quantum embedding using the Householder transformation: a multi-state extension based on ensembles

Cited by in corpus (2)

• Ensemble density functional theory of excited states: Exact N-centered formalism and practical opportunities
• Ghost Embedding Bridging Chemistry and One-Body Theories