50 citations · 118 across the 14 of their papers we have counts for
19 papers
Vertical ionization energies from inverse generalized Kohn-Sham calculations at fixed electron density
Vishal Subramanian, Bikash Kanungo, John P. Perdew +2
The exact Kohn--Sham (KS) system must have its highest occupied orbital energy equal to the negative of the lowest vertical ionization energy (VIE). No comparable theorem connects…
Machine-learned Laplacian-level density functional from exact exchange-correlation potentials and energies
Arghadwip Paul, Bikash Kanungo, Sambit Das +1
We present NNLap, a machine-learned Laplacian-level exchange-correlation (XC) functional that augments PBE with a neural-network correction depending on the electron density, its g…
Exchange-Correlation Potentials and Energies from Inverse Generalized Kohn-Sham Calculations
Vishal Subramanian, Bikash Kanungo, Vaibhav Khanna +2
The Kohn-Sham (KS) formulation of density functional theory (DFT) is a map from the many-electron problem to an effective single-electron problem that is governed by a local multip…
Large-scale pseudopotential density functional theory calculations using orthogonalized enriched finite element basis
Avirup Sircar, Bikash Kanungo, Sambit Das +1
We present an efficient and scalable computational framework for pseudopotential Kohn-Sham density functional theory (KS-DFT) calculations using an enriched finite element (EFE) ba…
Field theoretic atomistics: Learning thermodynamic and variational surrogate to density functional theory
Sambit Das, Bikash Kanungo, Arghadwip Paul +1
The Hohenberg-Kohn (HK) theorem -- the bedrock of density functional theory (DFT) -- establishes a universal map from the external potential to the energy. It also relates the elec…
invDFT: A CPU-GPU massively parallel tool to find exact exchange-correlation potentials from groundstate densities
Vishal Subramanian, Bikash Kanungo, Vikram Gavini
Density functional theory (DFT) remains the most widely used electronic structure method. Although exact in principle, in practice, it relies on approximations to the exchange-corr…
Exchange-Correlation Potentials and Energy Densities through Orbital Averaging and Aufbau Integration
Vaibhav Khanna, Bikash Kanungo, Jeffrey Hatch +2
Exchange-correlation potentials vxc and energy densities exc are derived for integer and fractional electron counts using an orbital-averaged Kohn-Sham inversion procedure. The ref…
Learning local and semi-local density functionals from exact exchange-correlation potentials and energies
Bikash Kanungo, Jeffrey Hatch, Paul M. Zimmerman +1
Finding accurate exchange-correlation (XC) functionals remains the defining challenge in density functional theory (DFT). Despite 40 years of active development, the desired chemic…
Accelerating inverse Kohn-Sham calculations using reduced density matrices
Bikash Kanungo, Soumi Tribedi, Paul M. Zimmerman +1
The Ryabinkin-Kohut-Staroverov (RKS) and Kanungo-Zimmerman-Gavini (KZG) methods offer two approaches to find exchange-correlation (XC) potentials from ground state densities. The R…
Exponential time propagators for elastodynamics
Paavai Pari, Bikash Kanungo, Vikram Gavini
We propose a computationally efficient and systematically convergent approach for elastodynamics simulations. We recast the second-order dynamical equation of elastodynamics into a…
Examining the Impact of Local Condition Violations on Energy Computations in DFT
Vaibhav Khanna, Bikash Kanungo, Vikram Gavini +2
This work introduces Extent of Violation Indices (EVIs), a novel metric for quantifying how well exchange-correlation functionals adhere to local conditions. Applying EVIs to a div…
Exact and model exchange-correlation potentials for open-shell systems
Bikash Kanungo, Jeffrey Hatch, Paul M. Zimmerman +1
The conventional approaches to the inverse density functional theory problem typically assume non-degeneracy of the Kohn-Sham (KS) eigenvalues, greatly hindering their use in open-…
Unconventional Error Cancellation Explains the Success of Hartree-Fock Density Functional Theory for Barrier Heights
Bikash Kanungo, Aaron D. Kaplan, Chandra Shahi +2
Energy barriers, which control the rates of chemical reactions, are seriously underestimated by computationally-efficient semi-local approximations for the exchange-correlation ene…
Exchange Correlation Potentials from Full Configuration Interaction in a Slater Orbital Basis
Soumi Tribedi, Duy-Khoi Dang, Bikash Kanungo +2
Ryabinkin-Kohut-Staroverov (RKS) theory builds a bridge between wave function theory and density functional theory by using quantities from the former to produce accurate exchange-…
Efficient all-electron time-dependent density functional theory calculations using an enriched finite element basis
Bikash Kanungo, Nelson D. Rufus, Vikram Gavini
We present an efficient and systematically convergent approach to all-electron real-time time-dependent density functional theory (TDDFT) calculations using a mixed basis, termed a…
A comparison of exact and model exchange-correlation potentials for molecules
Bikash Kanungo, Paul M. Zimmerman, Vikram Gavini
Accurate exchange-correlation (XC) potentials for 3-dimensional systems -- via solution of the \emph{inverse} density functional theory (DFT) problem -- are now available to test t…
Fast and robust all-electron density functional theory calculations in solids using orthogonalized enriched finite elements
Nelson D. Rufus, Bikash Kanungo, Vikram Gavini
We present a computationally efficient approach to perform systematically convergent real-space all-electron Kohn-Sham DFT calculations for solids using an enriched finite element…
Real-time time-dependent density functional theory using higher order finite element methods
Bikash Kanungo, Vikram Gavini
We present a computationally efficient approach to solve the time-dependent Kohn-Sham equations in real-time using higher-order finite-element spatial discretization, applicable to…
Large-scale all-electron density functional theory calculations using an enriched finite element basis
Bikash Kanungo, Vikram Gavini
We present a computationally efficient approach to perform large-scale all-electron density functional theory calculations by enriching the classical finite element basis with comp…