有限温度下具有强密度相关交换相关势的晶格密度泛函理论

环境对扩展强关联系统有效磁交换积分和局域谱的影响

Environment effects on effective magnetic exchange integrals and local spectroscopy of extended strongly correlated systems

本文分析了不同环境因素对强关联系统局域光谱的影响。我们发现，通常的形式电荷定义的电荷转移和Madelung势是太粗糙的嵌入碎片计算中的本地激发能的准确测定。提出了一个在无限大系统态密度下嵌入有效性的判据。

屏蔽交换动力学平均场论及其与密度泛函理论的关系：SrVO3和SrTiO3

Screened exchange dynamical mean field theory and its relation to density functional theory: SrVO3 and SrTiO3

我们提出的第一个应用程序最近提出的电子结构计划过渡金属氧化物：屏蔽交换动力学平均场论包括非局域交换超出局部密度近似和动力学相关超出标准的动力学平均场论。我们的光谱函数SrVO3的结果与现有的实验数据，包括光电子能谱和热力学一致。最后，3d 0化合物SrTiO 3作为一个测试案例，以说明如何理论减少到能带结构的标准电子结构技术的弱相关化合物。

含时密度泛函理论中具有记忆的局域交换关联矢势：广义流体力学方法

Local exchange-correlation vector potential with memory in Time-Dependent Density Functional Theory: the generalized hydrodynamics approach

利用朗道费米液体理论，我们推导出一个非线性非绝热近似的交换相关（xc）矢量势定义的xc应力张量。应力张量是一个局部非线性泛函的两个基本变量-位移矢量和二阶张量，它描述了演化的动量在一个局部框架与欧拉速度移动。对于无旋运动和平衡初始状态的张量变量的依赖减少到一个度量所产生的动力学变形的系统。

用于Hubbard模型的Kohn-Sham密度泛函理论的机器学习半局域交换关联泛函

Machine-learning semi-local exchange-correlation functionals for Kohn-Sham density functional theory of the Hubbard model

本研究利用机器学习构建了适用于一维自旋Hubbard模型的半局域交换关联泛函，通过泛函导数求解Kohn-Sham方程，并计算了线性链的极化率以逼近热力学极限。

由轨道相关耦合常数平均对关联函数构造的交换关联能泛函

Exchange-correlation energy functional constructed from orbital-dependent coupling-constant-averaged pair correlation functions

利用轨道相关耦合常数平均对关联函数，$ {\bar{g}}^{σσ'}({\bf r, r'})$，提出了密度泛函理论中的交换关联能泛函$ E_{\mathrm xc} $和相应的交换关联势$ v_{\mathrm xc}({\bf r}) $，用于原子、分子和固体的电子结构计算.这些与轨道相关的$ {\bar{g}}^{σσ'}({\bf r, r'})$满足对称性、泡利原理和求和规则。在均匀密度的限制$ {\bar{g}}^{σσ'}({\bf r, r'})$减少到非常准确的类似物的电子液体，从长和短距离之间的相关性，涉及交换校正插值获得。$ v_{\mathrm xc}({\bf r}) $的主要贡献是以电子与交换库仑空穴的库仑相互作用的形式给出的，本文的理论不仅保证了局域电荷中性，而且再现了有限体系交换势$ v_{\mathrm x}({\bf r}) = - e^2 / r $的精确渐近形式.本文处理关联的方法，如果适用于有限系统，甚至可以给出$ r^{-4} $阶关联势$ v_{\mathrm c}({\bf r}) $和$ r^{-6} $阶范德华势的渐近形式。

二维开壳层体系的交换能和关联能泛函

Exchange and correlation energy functionals for two-dimensional open-shell systems

我们考虑二维系统中交换能和关联能的密度泛函。的泛函是通过使用相应的交换和相关孔的角度平均值的精确约束，分别构造，并假设它们的特征尺寸之间的比例。电子电流和自旋明确考虑，使所得的泛函是适合于处理系统表现出轨道电流和/或自旋极化。我们的数值结果表明，在有限系统中，建议的泛函优于标准的二维局域自旋密度近似，仍然表现良好，也在均匀的二维电子气的重要限制。

二维B88交换能泛函的构造

Construction of the B88 exchange-energy functional in two dimensions

我们构造了有限二维系统交换能量密度的广义梯度近似。在非经验原则的指导下，我们包括适当的小梯度限制和适当的尾部交换空穴潜力。所观察到的性能优于二维局域密度近似，这强调了该方法在实际应用中的实用性。

强非均匀电子气中交换和关联的量子Monte Carlo分析

Quantum Monte Carlo Analysis of Exchange and Correlation in the Strongly Inhomogeneous Electron Gas

我们用变分量子蒙特卡罗方法计算了几个电子气系统的密度泛函交换关联空穴n_{xc}、交换关联能量密度e_{xc}和总交换关联能E_{xc}，在这些系统中，强密度不均匀性是由余弦波势引起的.我们将所得结果与局部密度近似和广义梯度近似进行了比较。据发现，非本地的贡献e_{xc}包含一个积极的重要组成部分，其大小，形状和符号是由电子密度的拉普拉斯控制。

载流态交换能泛函的高斯近似：在二维系统中的应用

Gaussian approximations for the exchange-energy functional of current-carrying states: Applications to two-dimensional systems

电子结构的计算通常是在密度泛函理论的框架内进行的，通常都取得了很大的成功。然而，对于降维的电子，仍然需要更好地近似交换相关能量泛函。此外，需要适当地描述载流状态的近似泛函的发展是一个额外的挑战。为了沿着这些方向取得进展，我们表明，简单而有效的交换能的表达式可以通过考虑的单体自旋密度矩阵的短程行为。几个二维系统的应用程序证实了所得到的近似的优良性能，并验证规范不变性的要求是非常重要的处理载流状态。

Machine Learning the Physical Non-Local Exchange-Correlation Functional of Density-Functional Theory

We train a neural network as the universal exchange-correlation functional of density-functional theory that simultaneously reproduces both the exact exchange-correlation energy and potential. This functional is extremely non-local, but retains the computational scaling of traditional local or semi-local approximations. It therefore holds the promise of solving some of the delocalization problems that plague density-functional theory, while maintaining the computational efficiency that characterizes the Kohn-Sham equations. Furthermore, by using automatic differentiation, a capability present …

Exact thermal density functional theory for a model system: Correlation components and accuracy of the zero-temperature exchange-correlation approximation

Thermal density functional theory calculations often use the Mermin-Kohn-Sham scheme, but employ ground-state approximations to the exchange-correlation (XC) free energy. In the simplest solvable nontrivial model, an asymmetric Hubbard dimer, we calculate the exact many-body energies and the exact Mermin-Kohn-Sham functionals for this system and extract the exact XC free energy. For moderate temperatures and weak correlation, we find this approximation to be excellent. We extract various exact free-energy correlation components and the exact adiabatic connection formula.

库仑阻塞的密度泛函描述：绝热或动态交换相关？

Density functional description of Coulomb blockade: Adiabatic or dynamic exchange-correlation?

在Kondo温度以上，Anderson结的Kohn-Sham零偏压电导已被证明完全错过库仑阻塞。在一个标准模型的谱函数，我们推导出一个参数化的现场交换相关电位和偏差下降的网站占领的函数，适用于所有的相关强度。我们用我们的研究结果播种怀疑的共同解释所产生的动态交换相关的贡献，这样的修正。

Exchange-correlation functionals of i-DFT for asymmetrically coupled leads

A recently proposed density functional approach for steady-state transport through nanoscale systems (called i-DFT) is used to investigate junctions which are asymmetrically coupled to the leads and biased with asymmetric voltage drops. In the latter case, the system can simply be transformed to a physically equivalent one with symmetric voltage drop by a total energy shift of the entire system. For the former case, known exchange correlation gate and bias functionals have to be generalized to take into account the asymmetric coupling to the leads. We show how differential conductance spectra …

Density-functional theory for systems with noncollinear spin: orbital-dependent exchange-correlation functionals and their application to the Hubbard dimer

A new class of orbital-dependent exchange-correlation (xc) potentials for applications in noncollinear spin-density-functional theory is developed. Starting from the optimized effective potential (OEP) formalism for the exact exchange potential - generalized to the noncollinear case - correlation effects are added via a self-consistent procedure inspired by the Singwi-Tosi-Land-Sjolander (STLS) method. The orbital-dependent xc potentials are applied to the Hubbard dimer in uniform and noncollinear magnetic fields and compared to exact diagonalization and to the Bethe-ansatz local spin-density …

含时密度泛函理论的标量交换关联核与张量交换关联核之间的关系

On the relation between the scalar and tensor exchange-correlation kernels of the time-dependent density-functional theory

标量$f_{xc}$和张量$\hat{f}_{xc}$交换相关（xc）核分别是含时密度泛函理论和含时电流密度泛函理论的关键成分。我们推导出一个相对简单的关系，这两个内核的假设下，动态XC可以被认为是“弱”。我们希望我们的公式能够作为直接进入许多应用的纯量$f_{xc}$和张量$\hat{f}_{xc}$之间的方便桥梁，张量由于其在空间中的位置，更容易逼近。

强关联系统交换关联泛函的不连续性--临界性

The discontinuous nature of the exchange-correlation functional -- critical for strongly correlated systems

交换相关泛函的标准近似在分数电荷的线性条件下会产生很大的误差，导致离域误差，而分数自旋的恒定条件会产生静态相关误差。对于分数电荷和分数自旋的状态，这两个条件现在是统一的：精确的能量泛函是一个平面，沿着分数电荷坐标是线性的，沿着分数自旋坐标是常数，在整数处有一条不连续的线。这揭示了导数不连续性的本质，并要求密度或轨道的显式不连续泛函超越目前使用的光滑近似。这是DFT应用于强关联系统的关键。

有限温度下约化密度矩阵泛函理论。II。应用于电子气体：仅交换

Reduced density matrix functional theory at finite temperature. II. Application to the electron gas: Exchange only

利用新近引入的有限温度约化密度矩阵泛函理论，我们将一级近似应用于均匀电子气。我们考虑共线自旋态以及对称性破缺态描述平面自旋螺旋和调查的磁相图以及温度依赖性的单粒子光谱。

低维纳米结构交换相关能的Laplacian能级密度泛函

Laplacian-level density functionals for the exchange-correlation energy of low-dimensional nanostructures

在低维电子纳米结构的建模中，电子-电子相互作用的评估是一项具有挑战性的任务。在这里，我们提出了一个准确和实用的密度泛函方法来解决二维多电子问题。特别是，我们表明，自旋密度泛函类的亚广义梯度近似可以大大简化减少显式依赖于Kohn-Sham轨道的依赖于电子自旋密度及其空间导数。对各种量子点系统的测试表明，通过修改，整体准确性即使没有提高，也得到了很好的保持。

First-principles calculations of magnetic states in pyrochlores using a source-corrected exchange and correlation functional

We present a first-principles investigation of the spin-ice state in Dy$_2$Ti$_2$O$_7$ using a magnetic source-free exchange and correlation functional, implemented in the Castep electronic-structure code. By comparing results from the conventional local spin-density approximation, we show that a spin-ice state in Dy$_2$Ti$_2$O$_7$ can be reliably obtained by removing the magnetic sources from the exchange and correlation contributions to the potential, and we contrast this against the computed ground states of other frustrated pyrochlore magnets.

混合密度泛函理论是否预言了δ-钚的非磁性基态？

Does hybrid density functional theory predict a non-magnetic ground state for delta-Plutonium?

杂化密度泛函理论（Hybrid density functional，简称HDFT）取代了部分密度泛函理论（density functional theory，简称DFT）中的精确Hartree-Fock（HF）交换，已被用于研究δ-钚的结构、磁性和电子性质。使用的精确Hartree-Fock交换分数为25%、40%和55%。与纯PBE泛函相比，PBE-HF杂化泛函的晶格常数相对于实验值有所扩展。对于55%的HF贡献，实现了非磁性的基态;否则，基态是反铁磁性的。5 f电子倾向于表现出轻微的离域或巡回的纯PBE功能和明确的本地化的混合功能，与5 f电子本地化的程度增加的HF交换量。总的来说，混合密度泛函的性能似乎并不优于纯密度泛函的delta-Plu。

Exchange-correlation magnetic fields in spin-density-functional theory

In spin-density-functional theory for noncollinear magnetic materials, the Kohn-Sham system features exchange-correlation (xc) scalar potentials and magnetic fields. The significance of the xc magnetic fields is not very well explored; in particular, they can give rise to local torques on the magnetization, which are absent in standard local and semilocal approximations. We obtain exact benchmark solutions for two electrons on four-site extended Hubbard lattices over a wide range of interaction strengths, and compare exact xc potentials and magnetic fields with approximations obtained from orb…

Weight Dependence of Local Exchange-Correlation Functionals in Ensemble Density-Functional Theory: Double Excitations in Two-Electron Systems

Gross--Oliveira--Kohn (GOK) ensemble density-functional theory (GOK-DFT) is a time-\textit{independent} extension of density-functional theory (DFT) which allows to compute excited-state energies via the derivatives of the ensemble energy with respect to the ensemble weights. Contrary to the time-dependent version of DFT (TD-DFT), double excitations can be easily computed within GOK-DFT. However, to take full advantage of this formalism, one must have access to a \textit{weight-dependent} exchange-correlation functional in order to model the infamous ensemble derivative contribution to the exc…

用含时密度泛函理论和带隙凝胶模型交换关联核计算固体的光谱

Optical spectra of solids obtained by time-dependent density-functional theory with the jellium-with-gap model exchange-correlation kernel

在从头算含时密度泛函理论（TD-DFT）的框架下，我们提出了一个基于带隙凝胶模型的交换相关核的静态近似。该核考虑了电子-空穴相互作用，并且能够解决强束缚激子和弱激子效应。TD-DFT吸收光谱的几种散装材料（半导体和绝缘体）的再现非常好的协议与实验和计算成本低。

密度矩阵-泛函理论中的Mueller交换关联能

Mueller's Exchange-Correlation Energy in Density-Matrix-Functional Theory

随着人们对Mueller密度矩阵泛函理论的兴趣日益浓厚，我们对其性质进行了系统的数学研究。该泛函类似于Hartree-Fock泛函，但具有修改的交换项，其中密度矩阵γ（X，X '）的平方被γ^{1/2}（X，X'）的平方代替。在对密度矩阵泛函理论进行了广泛的介绍性讨论之后，我们证明了该泛函是凸的（与HF泛函不同），并且能量最小化γ具有唯一的密度ρ（x），这是HF理论中经常缺少的物理理想性质。证明了极小元存在的充要条件是N \leq Z，并给出了极小能量和极小元的各种性质.我们还给出了γ轨道方程的精确描述，它比HF理论的更复杂。我们陈述了关于该理论的一些开放的数学问题，并给出了解答。

通过非均匀系统中交换关联空穴的显式模型实现非局域密度泛函

Towards non-local density functionals by explicit modeling of the exchange-correlation hole in inhomogeneous systems

我们提出了一种新的方法来发展一个非局域密度泛函的直接模拟的形状的交换相关（xc）洞在非均匀系统。该泛函的目的是给出一个准确的xc-能量和一个准确的相应的xc-潜力，即使在困难的近简并的情况下，如分子键断裂。我们特别要求：（1）xc空穴适当地含有-1电子，（2）xc势在有限系统外具有渐近的-1/r行为，（3）xc势具有与xc能量泛函的导数不连续性有关的正确的台阶结构.现有的泛函中没有一个满足所有这些要求。这些要求是通过以这样一种方式屏蔽交换孔来实现的，即成对关联函数是对称的并且满足求和规则。这两个特征直接意味着（1）和（2），而交换空穴对Kohn-Sham轨道的显式依赖性意味着（3）。初步计算表明，离解氢分子的物理描述得到了改进。虽然总能量还远未达到完美，但我们的非局域密度泛函的结合曲线比局域密度近似提供了显着的改进。