Stochastic embedding DFT: theory and application to p-nitroaniline

Abstract

Over this past decade, we combined the idea of stochastic resolution of identity with a variety of electronic structure methods. In our stochastic Kohn-Sham DFT method, the density is an average over multiple stochastic samples, with stochastic errors that decrease as the inverse square root of the number of sampling orbitals. Here we develop a stochastic embedding density functional theory method (se-DFT) that selectively reduces the stochastic error (specifically on the forces) for a selected sub-system(s). The motivation, similar to that of other quantum embedding methods, is that for many systems of practical interest the properties are often determined by only a small sub-system. In stochastic embedding DFT two sets of orbitals are used: a deterministic one associated with the embedded subspace, and the rest which is described by a stochastic set. The method is exact in the limit of large number of stochastic samples. We apply se-DFT to study a p-nitroaniline molecule in water, where the statistical errors in the forces on the system (the p-nitroaniline molecule) are reduced by an order of magnitude compared with non-embedding stochastic DFT.

References in corpus (10)

• Advanced capabilities for materials modelling with Quantum ESPRESSO
• Quantum embedding theories
• Self-averaging stochastic Kohn-Sham density functional theory
• Orbital-Free Density Functional Theory Implementation with the Projector Augmented-Wave Method
• Embedded density functional theory for covalently bonded and strongly interacting subsystems
• Embedded fragment stochastic density functional theory
• Stochastic Density Functional Theory at Finite Temperatures
• Sublinear scaling for time-dependent stochastic density functional theory
• Overlapped Embedded Fragment Stochastic Density Functional Theory for Covalently Bonded Materials
• Equilibrium configurations of large nanostructures using the embedded saturated-fragments stochastic density functional theory

Cited by in corpus (7)

• Fast and Universal Kohn Sham Density Functional Theory Algorithm for Warm Dense Matter to Hot Dense Plasma
• Decomposition and embedding in the stochastic $GW$ self-energy
• Mixed Stochastic-Deterministic Time-Dependent Density Functional Theory: Application to Stopping Power of Warm Dense Carbon
• Plane-Wave-Based Stochastic-Deterministic Density Functional Theory for Extended Systems
• Dopant levels in large nanocrystals using stochastic optimally tuned range-separated hybrid density functional theory
• Linear scalability of density functional theory calculations without imposing electron localization
• Compact Gaussian basis sets for stochastic DFT calculations