Ionic forces and stress tensor in all-electron DFT calculations using enriched finite element basis
arXiv:2205.07161 · doi:10.1103/PhysRevB.106.085108
Abstract
The enriched finite element basis -- wherein the finite element basis is enriched with atom-centered numerical functions -- has recently been shown to be a computationally efficient basis for systematically convergent all-electron DFT ground-state calculations. In this work, we present the expressions to compute variationally consistent ionic forces and stress tensor for all-electron DFT calculations in the enriched finite element basis. In particular, we extend the formulation of configurational forces in Motamarri & Gavini (Phys. Rev. B 2018) to the enriched finite element basis and elucidate the additional contributions arising from the enrichment functions. We demonstrate the accuracy of the formulation by comparing the computed forces and stresses for various benchmark systems with those obtained from finite-differencing the ground-state energy. Further, we also benchmark our calculations against Gaussian basis for molecular systems and against the LAPW+lo basis for periodic systems.
References in corpus (17)
- The SIESTA method for ab initio order-N materials simulation
- Efficient index handling of multidimensional periodic boundary conditions
- DFT-FE -- A massively parallel adaptive finite-element code for large-scale density functional theory calculations
- Force calculation and atomic-structure optimization for the full-potential linearized augmented plane-wave code WIEN
- Higher-order adaptive finite-element methods for Kohn-Sham density functional theory
- Real-space local polynomial basis for solid-state electronic-structure calculations: A finite-element approach
- Accurate ionic forces and geometry optimisation in linear scaling density-functional theory with local orbitals
- DFT-FE 1.0: A massively parallel hybrid CPU-GPU density functional theory code using finite-element discretization
- All-electron density functional theory and time-dependent density functional theory with high-order finite elements
- Large-scale all-electron density functional theory calculations using an enriched finite element basis
- A subquadratic-scaling subspace projection method for large-scale Kohn-Sham density functional theory calculations using spectral finite-element discretization
- Configurational forces in electronic structure calculations using Kohn-Sham density functional theory
- All-electron density functional calculations for electron and nuclear spin interactions in molecules and solids
- Real-time time-dependent density functional theory using higher order finite element methods
- On the calculation of the stress tensor in real-space Kohn-Sham Density Functional Theory
- Fast and robust all-electron density functional theory calculations in solids using orthogonalized enriched finite elements
- Orbital-enriched Flat-top Partition of Unity Method for the Schrödinger Eigenproblem