195 citations · 856 across the 41 of their papers we have counts for
14 papers · 1 filter
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…
Intrinsic ductility enhancement in Mg alloys elucidated via large-scale ab-initio calculations
Sambit Das, Vikram Gavini
Magnesium is the lightest structural alloy, yet its practical use is limited by its low ductility. Recent studies suggest ductility enhancement in dilute Mg alloys may stem from fa…
Quasicrystal bulk and surface energies from density functional theory
Woohyeon Baek, Sambit Das, Shibo Tan +2
Are quasicrystals stable or metastable? Density functional theory (DFT) is often used to evaluate thermodynamic stability, but quasicrystals are long-range aperiodic and their ener…
Tucker tensor approach for accelerating exchange computations in a real-space finite-element discretization of generalized Kohn-Sham density functional theory
Vishal Subramanian, Sambit Das, Vikram Gavini
The evaluation of Fock exchange is often the computationally most expensive part of hybrid functional density functional theory calculations in a systematically improvable, complet…
Accelerating self-consistent field iterations in Kohn-Sham density functional theory using a low rank approximation of the dielectric matrix
Sambit Das, Vikram Gavini
We present an efficient preconditioning technique for accelerating the fixed point iteration in real-space Kohn-Sham density functional theory (DFT) calculations. The preconditione…
Roadmap on Electronic Structure Codes in the Exascale Era
Vikram Gavini, Stefano Baroni, Volker Blum +38
Electronic structure calculations have been instrumental in providing many important insights into a range of physical and chemical properties of various molecular and solid-state…
Accurate approximations of density functional theory for large systems with applications to defects in crystalline solids
Kaushik Bhattacharya, Vikram Gavini, Michael Ortiz +2
This chapter presents controlled approximations of Kohn-Sham density functional theory (DFT) that enable very large scale simulations. The work is motivated by the study of defects…
LiCoO phase stability studied by machine learning-enabled scale bridging between electronic structure, statistical mechanics and phase field theories
Gregory H. Teichert, Sambit Das, Muratahan Aykol +3
LiO (TM={Ni, Co, Mn}) are promising cathodes for Li-ion batteries, whose electrochemical cycling performance is strongly governed by crystal structure and phase stability…
Spin-spin interactions in solids from mixed all-electron and pseudopotential calculations a path to screening materials for spin qubits
Krishnendu Ghosh, He Ma, Mykyta Onizhuk +2
Understanding the quantum dynamics of spin defects and their coherence properties requires accurate modeling of spin-spin interaction in solids and molecules, for example by using…
All-electron density functional calculations for electron and nuclear spin interactions in molecules and solids
Krishnendu Ghosh, He Ma, Vikram Gavini +1
The interaction between electronic and nuclear spins in the presence of external magnetic fields can be described by a spin Hamiltonian, with parameters obtained from first princip…
Electronic structure study of screw dislocation core energetics in Aluminum and core energetics informed forces in a dislocation aggregate
Sambit Das, Vikram Gavini
We use a real-space formulation of orbital-free DFT to study the core energetics and core structure of an isolated screw dislocation in Aluminum. Using a direct energetics based ap…
Real-space formulation of orbital-free density functional theory using finite-element discretization: The case for Al, Mg, and Al-Mg intermetallics
Sambit Das, Mrinal Iyer, Vikram Gavini
We propose a local real-space formulation for orbital-free DFT with density dependent kinetic energy functionals and a unified variational framework for computing the configuration…
Electronic-structure study of an edge dislocation in Aluminum and the role of macroscopic deformations on its energetics
Mrinal Iyer, Balachandran Radhakrishnan, Vikram Gavini
We employed a real-space formulation of orbital-free density functional theory using finite-element basis to study the defect-core and energetics of an edge dislocation in Aluminum…
Role of the defect-core in energetics of vacancies
Vikram Gavini
Electronic structure calculations at macroscopic scales are employed to investigate the crucial role of a defect-core in the energetics of vacancies in aluminum. We find that vacan…