DFT

PAW 赝势 SCF 收敛问题的诊断与修复

Published: 2026-05-19

将赝势从 norm-conserving(psp8,ta015)切换到 PAW(xml,PseudoDojo pbe/paw-sr-11,ta031)后,所有 COHP 计算的 SCF 迭代出现严重的收敛困难。能量在前几步快速下降后开始振荡上升,残差(vres2)在 $\sim1\times10^{-2}$ 处停滞不前。本文记录该问题的诊断与修复过程。

ABINIT 8.6.3 + LOBSTER 5.1.1 COHP 计算工作流

Published: 2026-05-17

本文档记录使用 ABINIT 8.6.3 计算波函数,配合 LOBSTER 5.1.1 进行 COHP(Crystal Orbital Hamilton Population)分析的完整流程,包括版本选择理由、关键参数设置、输入文件模板、资源估算及常见问题排查。

使用 Python/Matplotlib 绘制多元素吸附能曲线网格图

Published: 2026-05-01

在密度泛函理论(DFT)计算化学研究中,绘制 adatom(吸附原子)沿表面法线方向的吸附能曲线是分析表面催化性质的重要手段。本文介绍一个完整的 Python 脚本,利用 Matplotlib 将六种元素(N、H、C、Si、O、S)在四种吸附位点(Top、Bridge、fcc、hcp)上的 $\Delta E_{\mathrm{ads}}$ 曲线以 $3 \times 2$ 网格布局呈现,每个面板同时包含主图和局部放大图。

第一性原理计算中的结构优化:从入门经验到实战策略

Published: 2026-04-14

结构优化(structure optimization 或 structure relaxation)是第一性原理计算中最基础、也最容易"算了很久却不一定算对"的环节。它的目标是通过调整原子坐标、晶格形状或晶胞体积,使体系到达一个能量更低、受力更小的稳定构型。对于 VASP 而言,优化的自由度主要由 ISIF 控制,优化算法主要由 IBRION 控制,而是否收敛通常由 EDIFFG 等参数判断。

DFT 计算中的优化算法与 Mixing 算法详解

Published: 2026-04-08

密度泛函理论(DFT)是现代计算材料科学和量子化学的核心工具。在 DFT 计算流程中,优化算法与 Mixing 算法的效率直接决定了计算的收敛速度与精度。本文将系统梳理 DFT 计算中的三大类优化算法——混合算法(Mixing)、对角化算法(Diagonalization)和结构弛豫算法(Relaxation),深入剖析其数学原理、实现细节与适用场景。

DFT计算中SCF不收敛?一篇搞懂收敛机制与解决方案

Published: 2026-04-08

在密度泛函理论(DFT)计算中,**自洽场(Self-Consistent Field,简称 SCF)**的收敛问题是每一个计算化学和凝聚态物理研究者都会遇到的"经典难题"。本质上,DFT 里的 SCF 收敛就是在解一个非线性不动点方程,通过"电荷/势的迭代 + 混合 + 预条件"把电子密度和哈密顿算符做到自洽。本文将深入剖析 SCF 迭代的收敛机制、不收敛的根本原因,以及针对不同体系的具体解决策略。

如何校准 ABINIT 中的 nband 参数

Published: 2026-03-31

在基于密度泛函理论(DFT)的第一性原理计算中,合理设置能带数量(nband)是确保计算准确性和效率的关键参数。本文将详细介绍如何根据体系中的价电子数量和材料特性,系统地校准 ABINIT 软件中的 nband 参数。

如何快速上手电子结构分析

Published: 2026-03-31

电子结构分析是理解材料物理化学性质的核心工具。由于电子运动极快且尺度微小,我们必须借助量子力学的概念,将电子视为波来进行分析。本文将系统介绍电子结构分析的核心要点和高效学习方法,帮助初学者快速入门。

深入理解 PAW 方法:计算资源与效率的平衡

Published: 2026-03-31

在基于密度泛函理论(DFT)的第一性原理计算中,伪势方法的选择直接影响计算的精度和效率。PAW(投影缀加波)方法和 NCPP(范数守恒伪势)是两种常用的伪势方案,它们在计算资源需求和实际运行效率上各有特点。本文将深入分析这两种方法的差异,帮助读者理解如何在实际计算中做出合理选择。

Abinit 自旋计算教程指导

Published: 2026-01-26

这篇博文旨在指导大家深入学习 Abinit 的自旋(Spin)教程。这部分内容对于研究磁性材料(如铁、钴、镍)或涉及重元素的自旋轨道耦合效应至关重要。我们将通过密度泛函理论(DFT)处理电子自旋的三种主要场景:铁磁性、反铁磁性以及自旋轨道耦合。

The Impact of chksymbreak=0 on K-Point Grid Symmetry in ABINIT: A Comprehensive Analysis

Published: 2025-11-16

Understanding the role of symmetry in density functional theory calculations is crucial for accurate and efficient materials modelling. The chksymbreak parameter in ABINIT controls how the software handles k-point grid symmetry breaking, with profound implications for both ground-state and response function calculations. This article examines its effects across different calculation types and provides evidence-based guidance for optimal usage.

Extracting Optimised Structures from ABINIT Output Files Using Abipy

Published: 2025-11-16

This guide demonstrates how to extract optimised crystal structures from ABINIT's NetCDF output files using the Abipy library. The workflow presented here simplifies the process of retrieving final geometries, tracking optimisation trajectories, and exporting structures in multiple formats for further analysis.

ABINIT Calculations for Aluminium Systems

Published: 2025-11-15

This article presents a series of sophisticated ABINIT input files demonstrating multi-dataset calculation techniques for aluminium systems, including k-point convergence studies, smearing temperature optimisation, and structural relaxation across diverse crystallographic configurations from bulk FCC to extended slab geometries.

ABINIT Configuration with UDTSET for Hydrogen Simulations

Published: 2025-11-15

This guide examines advanced dataset configuration techniques in ABINIT, demonstrating how the UDTSET feature enables efficient parametric studies and convergence testing through systematic variation of input parameters across multiple datasets in hydrogen molecular and atomic systems.

ABINIT Input Files for Hydrogen Simulations

Published: 2025-11-15

This post provides a look into the structure of an input file for ABINIT, a software package used for calculating the properties of materials. We will break down a multi-dataset input file for a simple Hydrogen system to understand the purpose of various key parameters.

ABINIT Calculations for Silicon

Published: 2025-11-15

This guide presents a series of ABINIT input file examples for silicon calculations, demonstrating various computational workflows including k-point convergence studies, structural optimisation, and band structure calculations. These examples illustrate the effective use of multi-dataset functionality to streamline complex computational tasks in density functional theory.

Getting Started with FAIRChem

Published: 2025-10-14

FAIRChem is a powerful machine learning framework developed by Meta AI for accelerating materials discovery and catalysis research. This comprehensive guide walks you through using FAIRChem, from exploring the web-based demo to performing local energy calculations on macOS.

Setting Up a Conda Environment for Scientific Computations (DFT)

Published: 2025-10-02

Setting up a reproducible computational environment is crucial for density functional theory (DFT) calculations and materials science research. This guide walks you through creating a dedicated Conda environment equipped with essential tools for DFT analysis, visualization, and machine learning applications in computational chemistry.