244 citations · 1.2k across the 20 of their papers we have counts for
21 papers
Elucidation of the subcritical character of the liquid--liquid transition in dense hydrogen
Valentin V. Karasiev, Joshua Hinz, S. X. Hu +1
The liquid-liquid phase transition in high-pressure Hydrogen is a problem of longstanding and controversy. The recent Nature paper by Cheng et al. [vol. 585, p. 217] makes a set of…
Carbon-Doped Sulfur Hydrides as Room-Temperature Superconductors at 270 GPa
S. X. Hu, R. Paul, V. V. Karasiev +1
To understand the most-recent experiment on room-temperature superconductivity in carbonaceous sulfur hydride (CSH) systems under high pressure, we have performed extensive stoichi…
Electronic structure of semiconductor nanoparticles from stochastic evaluation of imaginary-time path integral
Andrei Kryjevski, Thomas Luu, Valentin Karasiev
In the Kohn-Sham orbital basis imaginary-time path integral for electrons in a semiconductor nanoparticle has a mild Fermion sign problem and is amenable to evaluation by the stand…
Fully Consistent Density Functional Theory Determination of the Insulator-Metal Transition Boundary in Warm Dense Hydrogen
Joshua Hinz, Valentin V. Karasiev, S. X. Hu +4
Using conceptually and procedurally consistent density functional theory (DFT) calculations with an advanced meta-GGA exchange-correlation functional in ab initio molecular dynamic…
Towards accurate orbital-free simulations: a generalized gradient approximation for the non-interacting free energy density functional
Kai Luo, Valentin V. Karasiev, S. B. Trickey
For orbital-free {\it ab initio} molecular dynamics, especially on systems in extreme thermodynamic conditions, we provide the first pseudo-potential-adapted generalized gradient a…
A Simple Generalized Gradient Approximation for the Non-interacting Kinetic Energy Density Functional
K. Luo, V. V. Karasiev, S. B. Trickey
A simple, novel, non-empirical, constraint-based orbital-free generalized gradient approximation (GGA) non-interacting kinetic energy density functional is presented along with ill…
Kubo-Greenwood Electrical Conductivity Formulation and Implementation for Projector Augmented Wave Datasets
L. Calderin, V. V. Karasiev, S. B. Trickey
As the foundation for a new computational implementation, we survey the calculation of the complex electrical conductivity tensor based on the Kubo-Greenwood (KG) formalism (J.\ Ph…
Comment on "Communication: Simple and accurate uniform electron gas correlation energy for the full range of densities" [J. Chem. Phys. 145, 021101 (2016)]
Valentin V. Karasiev
A simple expression for the uniform electron gas (UEG) correlation energy, recently presented in Ref. [J. Chem. Phys. 145, 021101 (2016)], deviates from the reference quantum Monte…
Study of Some Simple Approximations to the Non-Interacting Kinetic Energy Functional
Edison X. Salazar, Pedro F. Guarderas, Eduardo V. Ludeña +2
Within the framework of density functional theory, we present a study of approximations to the enhancement factor of the non-interacting kinetic energy functional . For thi…
The importance of finite-temperature exchange-correlation for warm dense matter calculations
Valentin V. Karasiev, Lázaro Calderín, S. B. Trickey
Effects of explicit temperature dependence in the exchange-correlation (XC) free-energy functional upon calculated properties of matter in the warm dense regime are investigated. T…
System-Size Dependence in Grand Canonical and Canonical Ensembles
Debajit Chakraborty, James Dufty, Valentin V. Karasiev
The thermodynamics for a system with given temperature, density, and volume is described by the Canonical ensemble. The thermodynamics for a corresponding system with the same temp…
Frank Discussion of the Status of Ground-state Orbital-free DFT
Valentin V. Karasiev, S. B. Trickey
F.E. Harris has been a significant partner in our work on orbital-free density functional approximations for use in ab initio molecular dynamics. Here we mention briefly the essent…
Improved analytical representation of combinations of Fermi-Dirac integrals for finite-temperature density functional calculations
Valentin V. Karasiev, Debajit Chakraborty, S. B. Trickey
Smooth, highly accurate analytical representations of Fermi-Dirac (FD) integral combinations important in free-energy density functional calculations are presented. Specific forms…
Finite-temperature orbital-free DFT molecular dynamics: coupling Profess and Quantum Espresso
Valentin V. Karasiev, Travis Sjostrom, S. B. Trickey
Implementation of orbital-free free-energy functionals in the Profess code and the coupling of Profess with the Quantum Espresso code are described. The combination enables orbital…
Local Spin-density Approximation Exchange-correlation Free-energy Functional
Valentin V. Karasiev, Travis Sjostrom, James Dufty +1
An accurate analytical parametrization for the exchange-correlation free energy of the homogeneous electron gas, including interpolation for partial spin-polarization, is derived v…
Non-empirical Generalized Gradient Approximation Free Energy Functional for Orbital-free Simulations
Valentin V. Karasiev, Debajit Chakraborty, Olga A. Shukruto +1
We report the first wholly non-empirical generalized gradient approximation, non-interacting free energy functional for orbital-free density functional theory and use that new func…
Numerical local "hybrid" functional treatment of selected diatomic molecules: comparison of energies and multipole moments to conventional hybrid functionals
Ivan A. Mikhailov, Olga A. Shukruto, Artem E. Masunov +1
New local "hybrid" functionals proposed by V. V. Karasiev in [J. Chem. Phys. {\bf 118}, 8567 (2003)] are benchmarked against nonlocal hybrid functionals. Their performance is teste…
Comparison of Density Functional Approximations and the Finite-temperature Hartree-Fock Approximation in Warm Dense Lithium
Valentin V. Karasiev, Travis Sjostrom, S. B. Trickey
We compare the behavior of the finite-temperature Hartree-Fock model with that of thermal density functional theory using both ground-state and temperature-dependent approximate ex…
Application of self-consistent method to improve the performance of model exchange potentials
Valentin V. Karasiev, Eduardo V. Ludeña, Artëm E. Masunov
Self interaction error remains an impotrant problem in density functional theory. A number of approximations to exact exchange aimed to correct for this error while retainining com…
Issues and Challenges in Orbital-free Density Functional Calculations
V. V. Karasiev, S. B. Trickey
Solving the Euler equation which corresponds to the energy minimum of a density functional expressed in orbital-free form involves related but distinct computational challenges. On…
The Standard Model in Strong Fields: Electroweak Radiative Corrections for Highly Charged Ions
I. Bednyakov, L. Labzowsky, G. Plunien +2
Electroweak radiative corrections to the matrix elements are calculated for highly charged hydrogenlike ions. These matrix elements constitute…