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We present a comprehensive convergence analysis for Self-Consistent Field (SCF) iteration to solve a class of nonlinear eigenvalue problems with eigenvector-dependency (NEPv). Using a tangent-angle matrix as an intermediate measure for…

数值分析 · 数学 2020-09-22 Zhaojun Bai , Ren-Cang Li , Ding Lu

It is well known that the self-consistent field (SCF) iteration for solving the Kohn-Sham (KS) equation often fails to converge, yet there is no clear explanation. In this paper, we investigate the SCF iteration from the perspective of…

计算物理 · 物理学 2013-12-02 Xin Liu , Xiao Wang , Zaiwen Wen , Yaxiang Yuan

The Hartree-Fock equation is a fundamental equation in many-electron problems. It is of practical importance in quantum chemistry to find solutions to the Hartree-Fock equation. The self-consistent field (SCF) method is a standard numerical…

偏微分方程分析 · 数学 2023-11-17 Sohei Ashida

A new framework is presented for evaluating the performance of self-consistent field methods in Kohn-Sham density functional theory. The aims of this work are two-fold. First, we explore the properties of Kohn-Sham density functional theory…

计算物理 · 物理学 2019-07-18 Nick Woods , Phil Hasnip , Mike Payne

This article is concerned with the numerical solution of subspace optimization problems, consisting of minimizing a smooth functional over the set of orthogonal projectors of fixed rank. Such problems are encountered in particular in…

数值分析 · 数学 2022-10-17 Eric Cancès , Gaspard Kemlin , Antoine Levitt

The self-consistent field (SCF) iteration, combined with its variants, is one of the most widely used algorithms in quantum chemistry. We propose a procedure to adapt the SCF iteration for the p-Laplacian eigenproblem, which is an important…

数值分析 · 数学 2021-11-23 Parikshit Upadhyaya , Elias Jarlebring , Francesco Tudisco

The convergence property of a stochastic algorithm for the self-consistent field (SCF) calculations of electron structures is studied. The algorithm is formulated by rewriting the electron charges as a trace/diagonal of a matrix function,…

数值分析 · 数学 2023-04-20 Taehee Ko , Xiantao Li

In many iterative optimization methods, fixed-point theory enables the analysis of the convergence rate via the contraction factor associated with the linear approximation of the fixed-point operator. While this factor characterizes the…

系统与控制 · 电气工程与系统科学 2022-06-22 Trung Vu , Raviv Raich

A uniform derivation is presented of the self-consistent field equations in a finite basis set. Both restricted and unrestricted Hartree-Fock (HF) theory as well as various density functional (DF) approximations are considered. The unitary…

计算物理 · 物理学 2020-03-10 Susi Lehtola , Frank Blockhuys , Christian Van Alsenoy

In a recent letter [Europhys. Lett. 95, 13001 (2011)] the question of whether the density of a time-dependent quantum system determines its external potential was reformulated as a fixed point problem. This idea was used to generalize the…

量子物理 · 物理学 2013-08-05 M. Ruggenthaler , K. J. H Giesbertz , M. Penz , R. van Leeuwen

The convergence of the Conjugate Gradient method is subject to a locality limitation which imposes a lower bound on the number of iterations required before a qualitatively accurate approximation can be obtained. This limitation originates…

数值分析 · 数学 2026-01-16 Ulrich Rüde

This paper develops a fixed-point iteration to solve the steady-state water flow equations in an urban water distribution network. The fixed-point iteration is derived upon the assumption of turbulent flow solutions and the validity of the…

系统与控制 · 计算机科学 2018-07-05 Mohammadhafez Bazrafshan , Nikolaos Gatsis , Marcio Giacomoni , Ahmad Taha

A Josephson junction can be subjected to a local, strongly inhomogeneous magnetic field in various experimental situations. Here this problem is analyzed analytically and numerically. A modified sine-Gordon type equation in the presence of…

超导电性 · 物理学 2020-04-29 V. M. Krasnov

In the recent paper [17] the first experimental determination of the density matrix of a free electron beam has been reported. The employed method leads to a linear inverse problem with a positive semidefinite operator as unknown. The…

偏微分方程分析 · 数学 2020-02-19 Cong Shi , Claus Ropers , Thorsten Hohage

The density functional theory (DFT) in electronic structure calculations can be formulated as either a nonlinear eigenvalue or direct minimization problem. The most widely used approach for solving the former is the so-called…

计算物理 · 物理学 2013-08-14 Xin Zhang , Jinwei Zhu , Zaiwen Wen , Aihui Zhou

For optimal power flow problems with chance constraints, a particularly effective method is based on a fixed point iteration applied to a sequence of deterministic power flow problems. However, a priori, the convergence of such an approach…

最优化与控制 · 数学 2023-12-13 Johannes J. Brust , Mihai Anitescu

We prove that the fixed point iteration of arbitrary positive concave mappings with nonempty fixed point set converges geometrically for any starting point. We also show that positivity is crucial for this result to hold, and the concept of…

最优化与控制 · 数学 2022-10-19 Tomasz Piotrowski , Renato L. G. Cavalcante

We propose a novel adaptive damping algorithm for the self-consistent field (SCF) iterations of Kohn-Sham density-functional theory, using a backtracking line search to automatically adjust the damping in each SCF step. This line search is…

材料科学 · 物理学 2022-03-14 Michael F. Herbst , Antoine Levitt

The quantum mechanical ground state of electrons is described by Density Functional Theory, which leads to large minimization problems. An efficient minimization method uses a selfconsistent field (SCF) solution of large eigenvalue…

材料科学 · 物理学 2007-05-23 Claus Bendtsen , Ole H. Nielsen , Lars B. Hansen

The spectral density of various ensembles of sparse symmetric random matrices is analyzed using the cavity method. We consider two cases: matrices whose associated graphs are locally tree-like, and sparse covariance matrices. We derive a…

无序系统与神经网络 · 物理学 2009-11-13 Tim Rogers , Koujin Takeda , Isaac Pérez Castillo , Reimer Kühn
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