Compositional phase stability of correlated electron materials within DFT+DMFT

Abstract

Predicting the compositional phase stability of strongly correlated electron materials is an outstanding challenge in condensed matter physics, requiring precise computations of total energies. In this work, we employ the density functional theory plus dynamical mean-field theory (DFT+DMFT) formalism to address local correlations due to transition metal d electrons on compositional phase stability in the prototype rechargeable battery cathode material LixCoO2, and detailed comparisons are made with the simpler DFT+U approach (i.e. the Hartree-Fock solution of the DMFT impurity problem). Local interactions are found to strongly impact the energetics of the band insulator LiCoO2, most significantly via the Eg orbitals, which are partially occupied via hybridization with O p states. We find CoO2 and Li1/2CoO2 to be moderately correlated Fermi liquids with quasiparticle weights of 0.6-0.8 for the T2g states, which are most impacted by the interactions. As compared to DFT+U, DFT+DMFT considerably dampens the increase in total energy as U is increased, which indicates that dynamical correlations are important to describe this class of materials despite the relatively modest quasiparticle weights. Unlike DFT+U, which can incorrectly drive LixCoO2 towards spurious phase separating or charge ordered states, DFT+DMFT correctly captures the system's phase stability and does not exhibit a strong charge ordering tendency. Most importantly, the error within DFT+U varies strongly as the composition changes, challenging the common practice of artificially tuning U within DFT+U to compensate the errors of Hartree-Fock. DFT+DMFT predicts the average intercalation voltage decreases relative to DFT, opposite to the result of DFT+U, which would yield favorable agreement with experiment in conjunction with the overprediction of the voltage by the strongly constrained and appropriately normed DFT functional.

References in corpus (42)

• Wannier90: A Tool for Obtaining Maximally-Localised Wannier Functions
• Electronic Structure Calculations with Dynamical Mean-Field Theory: A Spectral Density Functional Approach
• Continuous-time Monte Carlo methods for quantum impurity models
• First-principles prediction of redox potentials in transition-metal compounds with LDA+U
• Quantum Monte Carlo Impurity Solver for Cluster DMFT and Electronic Structure Calculations in Adjustable Base
• Dynamical Mean-Field Theory within the Full-Potential Methods: Electronic structure of Ce-115 materials
• Implementation of the Projector Augmented Wave LDA+U Method: Application to the Electronic Structure of NiO
• Strongly Correlated Materials
• The Cerium volume collapse: Results from the LDA+DMFT approach
• Performance of the strongly constrained and appropriately normed density functional for solid-state materials
• Calibrating transition metal energy levels and oxygen bands in first principles calculations: accurate prediction of redox potentials and charge transfer in lithium transition metal oxides
• Self-consistency over the charge-density in dynamical mean-field theory: a linear muffin-tin implementation and some physical implications
• The alpha-gamma transition of Cerium is entropy-driven
• Importance of electronic correlations for structural and magnetic properties of the iron pnictide superconductor LaFeAsO
• Free energy from stationary implementation of the DFT+DMFT functional
• Calculated phonon spectra of paramagnetic iron at the alpha-gamma phase transition
• Total energy calculations using DFT+DMFT: computing the pressure phase diagram of the rare earth nickelates
• Computing total energies in complex materials using charge self-consistent DFT+DMFT
• Electronic phase diagram of the layered cobalt oxide system, LixCoO2 (0.0 <= x <= 1.0)
• Correlation effects in total energy of transition metals and related properties
• Covalency, double-counting and the metal-insulator phase diagram in transition metal oxides
• Doping effects on the electronic and structural properties of CoO2: An LSDA+U study
• Approaching finite-temperature phase diagrams of strongly correlated materials: a case study for V2O3
• Structural relaxation due to electronic correlations in the paramagnetic insulator KCuF3
• The Role of hybridization in NaxCoO2 and the Effect of Hydration
• Synthesis and properties of CoO2, the x = 0 end member of the LixCoO2 and NaxCoO2 systems
• Computation of correlation-induced atomic displacements and structural transformations in paramagnetic KCuF3 and LaMnO3
• Combined local-density and dynamical mean field theory calculations for the compressed lanthanides Ce, Pr, and Nd
• Electronic Correlations in CoO2, the Parent Compound of Triangular Cobaltates
• Mott Transition and Magnetism in Rare Earth Nickelates and its Fingerprint on the X-ray Scattering
• Charge self-consistent many-body corrections using optimized projected localized orbitals
• Density Functional plus Dynamical Mean-Field Theory of the Spin-Crossover Molecule Fe(phen)${}_2$(NCS)${}_2$
• Thermodynamics of the α-γ transition in Cerium from first principles
• Dynamical mean-field approach to materials with strong electronic correlations
• Density functional plus dynamical mean field theory of the metal-insulator transition in early transition metal oxides
• Magnetic and Electronic Properties of Li${}_x$CoO${}_2$ Single Crystals
• The phonon softening due to melting of the ferromagnetic order in elemental iron
• Measurement of electron correlations in LixCoO2 (x=0.0 - 0.35) using 59Co nuclear magnetic resonance and nuclear quadrupole resonance techniques
• Large effects of subtle electronic correlations on the energetics of vacancies in alpha-Fe
• Electronic phase diagram of LixCoO2 revisited with potentiostatically de-intercalated single crystals
• Compositional phase stability of strongly correlated electron materials within DFT+$U$
• The failure of DFT-based computations for a stepped-substrate-supported correlated Co wire

Cited by in corpus (4)

• Advances in actinide thin films: synthesis, properties, and future directions
• The importance of electronic correlations in exploring the exotic phase diagram of layered Li${}_x$MnO${}_2$
• Self-regulated ligand-metal charge transfer upon lithium ion de-intercalation process from LiCoO2 to CoO2
• Effect of Off-Diagonal Elements in Wannier Hamiltonian on DFT+DMFT for low-symmetry material: Study of Li${}_2$MnO${}_3$