50 citations · 118 across the 14 of their papers we have counts for
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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…
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…
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…
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…