Importance of charge self-consistency in first-principles description of strongly correlated systems  

作　　者：Swagata Acharya Dimitar Pashov Alexander N.Rudenk Malte Rösner Mark van Schilfgaarde Mikhail I.Katsnelson 

机构地区：[1]Institute for Molecules and Materials,Radboud University,Nijmegen 6525 AJ,The Netherlands [2]Theory and Simulation of Condensed Matter,King's College London,The Strand,London WC2R2LS,UK [3]National Renewable Energy Laboratory,Golden,80401 Colorado,USA

出　　处：《npj Computational Materials》2021年第1期1949-1956,共8页计算材料学（英文）

基　　金：M.I.K.,A.N.R.,and S.A.are supported by the ERC Synergy Grant,project 854843 FASTCORR(Ultrafast dynamics of correlated electrons in solids);M.v.S.and D.P.weresupported in the late stages of this work by the U.S.Department of Energy,Office of Science,Basic Energy Sciences under award FWP ERW7906.We acknowledge PRACE for awarding us access to Irene-Rome hosted by TGCC,France and Juwels Booster and Cluster,Germany.This work was also partly carried out on the Dutch national e-infrastructure with the support of SURF Cooperative.

摘　　要：First-principles approaches have been successful in solving many-body Hamiltonians for real materials to an extent when correlations are weak or moderate.As the electronic correlations become stronger often embedding methods based on first-principles approaches are used to better treat the correlations by solving a suitably chosen many-body Hamiltonian with a higher level theory.The success of such embedding theories,often referred to as second-principles,is commonly measured by the quality of self-energy E which is either a function of energy or momentum or both.However,E should,in principle,also modify the electronic eigenfunctions and thus change the real space charge distribution.While such practices are not prevalent,some works that use embedding techniques do take into account these effects.In such cases,choice of partitioning,of the parameters defining the correlated Hamiltonian,of double-counting corrections,and the adequacy of low-level Hamiltonian hosting the correlated subspace hinder a systematic and unambiguous understanding of such effects.Further,for a large variety of correlated systems,strong correlations are largely confined to the charge sector.Then an adequate non local low-order theory is important,and the high-order local correlations embedding contributes become redundant.Here we study the impact of charge self-consistency within two example cases,TiSez and CrBrs,and show how real space charge re-distribution due to correlation effects taken into.account within a first-principles Green's function-based many-body perturbative approach is key in driving qualitative changes to the final electronic structure of these materials.

关 键 词：theory CHARGE PRINCIPLES 

分 类 号：TB30[一般工业技术—材料科学与工程]