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John P Perdew - One of the best experts on this subject based on the ideXlab platform.
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accurate and numerically efficient r 2 scan meta Generalized Gradient Approximation
Bulletin of the American Physical Society, 2021Co-Authors: James W Furness, John P Perdew, Aaron D Kaplan, Jinliang Ning, Jianwei SunAbstract:The recently proposed rSCAN functional [J. Chem. Phys. 150, 161101 (2019)] is a regularized form of the SCAN functional [Phys. Rev. Lett. 115, 036402 (2015)] that improves SCAN's numerical performance at the expense of breaking constraints known from the exact exchange-correlation functional. We construct a new meta-Generalized Gradient Approximation by restoring exact constraint adherence to rSCAN. The resulting functional maintains rSCAN's numerical performance while restoring the transferable accuracy of SCAN.
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accurate and numerically efficient r2scan meta Generalized Gradient Approximation
Journal of Physical Chemistry Letters, 2020Co-Authors: James W Furness, John P Perdew, Aaron D Kaplan, Jinliang Ning, Jianwei SunAbstract:The recently proposed rSCAN functional [ J. Chem. Phys. 2019 150, 161101] is a regularized form of the SCAN functional [ Phys. Rev. Lett. 2015 115, 036402] that improves SCAN’s numerical performanc...
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Rehabilitation of the Perdew-Burke-Ernzerhof Generalized Gradient Approximation for layered materials
Physical Review B, 2017Co-Authors: Haowei Peng, John P PerdewAbstract:The structural and energetic properties of layered materials present a challenge to density functional theory with common semilocal Approximations to the exchange-correlation energy. By combining the most widely used semilocal Generalized Gradient Approximation (GGA), the Perdew-Burke-Ernzerhof (PBE) one, with the revised Vydrov--van Voorhis nonlocal correlation functional (rVV10), both excellent structural and energetic properties of 28 layered materials have been recovered with a judicious parameter selection. We term the resulting functional PBE+rVV10L, with the ``L'' indicating that it is for layered materials. Such a combination is not new, and only involves refitting a single global parameter. However, the resulting excellent accuracy suggests such a dispersion-corrected PBE for many aspects of theoretical studies on layered materials. For comparison, we also present the results for PBE+rVV10 where the parameter is determined by 22 interaction energies between molecules.
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versatile van der waals density functional based on a meta Generalized Gradient Approximation
Physical Review X, 2016Co-Authors: Haowei Peng, John P Perdew, Zenghui Yang, Jianwei SunAbstract:Van der Waals interactions are ubiquitous in different materials yet not always described properly by current theories. Now, researchers have determined how to accurately and efficiently treat long-range Van der Waals interactions together with other chemical bonds, new findings that are important for studies of layered materials.
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self consistent meta Generalized Gradient Approximation within the projector augmented wave method
Physical Review B, 2011Co-Authors: Jianwei Sun, Adrienn Ruzsinszky, Gabor I Csonka, Martijn Marsman, Pan Hao, Yoon Suk Kim, Georg Kresse, John P PerdewAbstract:The Tao-Perdew-Staroverov-Scuseria (TPSS) meta-Generalized-Gradient-Approximation (MGGA) and its revised version, the revTPSS, are implemented self-consistently within the framework of the projectoraugmented-wave (PAW) method, using a plane wave basis set. Both TPSS and revTPSS yield accurate atomization energies for the molecules in the AE6 set, better than those of the standard Perdew-Burke-Ernzerhof (PBE) Generalized-Gradient-Approximation. For lattice constants and bulk moduli of 20 diverse solids, revTPSS performs much better than PBE, and on average as well as PBEsol and Armiento-Mattsson (AM05), GGAs designed for solids. The latter two overestimate the atomization energies for molecules to an unacceptable degree. However, the revTPSS presents only a slight improvement over PBEsol for the prediction of cohesive energies for solids, and some deterioration with respect to PBE. We also study the magnetic properties of Fe, for which both TPSS and revTPSS predict the right ground-state solid phase, the ferromagnetic body-centered-cubic (bcc) structure, with an accurate magnetic moment. DOI: 10.1103/PhysRevB.84.035117
S. B. Trickey - One of the best experts on this subject based on the ideXlab platform.
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negative electron affinities and derivative discontinuity contribution from a Generalized Gradient Approximation exchange functional
Journal of Physical Chemistry A, 2020Co-Authors: Javier Carmonaespindola, Alberto Vela, Jose L Gazquez, S. B. TrickeyAbstract:Two methods to calculate negative electron affinities systematically from ground-state density functional methods are presented. One makes use of the LUMO (lowest unoccupied molecular orbital) energy shift provided by approximate inclusion of derivative discontinuity in the NCAP (nearly correct asymptotic potential) non-empirical, constraint-based Generalized Gradient Approximation (GGA) exchange functional. The other uses a second-order perturbation calculation of the derivative discontinuity based on the NCAP exchange-correlation potential. On a set of thirty-eight molecules, NCAP leads to a rather accurate description that is improved further through the perturbation correction. The results presented show the importance of the asymptotic behavior of the XC potential in the calculation of negative electron affinities as well as demonstrating the versatility of the NCAP functional.
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a simple Generalized Gradient Approximation for the noninteracting kinetic energy density functional
Physical Review B, 2018Co-Authors: Kai Luo, Valentin V. Karasiev, S. B. TrickeyAbstract:A simple, unconventional, nonempirical, constraint-based orbital-free Generalized Gradient Approximation (GGA) noninteracting kinetic energy density functional is presented along with illustrative applications. The innovation is adaptation of constraint-based construction to the essential properties of pseudodensities from the pseudopotentials that are essential in plane-wave-basis ab initio molecular dynamics. This contrasts with constraining to the qualitatively different Kato-cusp-condition densities. The single parameter in the proposed functional is calibrated by satisfying Pauli potential positivity constraints for pseudoatom densities. In static lattice tests on simple metals and semiconductors, the LKT (for the authors' initials) functional outperforms the previous best constraint-based GGA functional, VT84F [Phys. Rev. B 88, 161108(R) (2013)], is generally superior to a recently proposed meta-GGA, is reasonably competitive with parametrized two-point functionals, and is substantially faster.
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a simple Generalized Gradient Approximation for the noninteracting kinetic energy density functional
Physical Review B, 2018Co-Authors: Kai Luo, Valentin V. Karasiev, S. B. TrickeyAbstract:A simple, novel, non-empirical, constraint-based orbital-free Generalized Gradient Approximation (GGA) non-interacting kinetic energy density functional is presented along with illustrative applications. The innovation is adaptation of constraint-based construction to the essential properties of pseudo-densities from the pseudo-potentials that are essential in plane-wave-basis {\it ab initio} molecular dynamics. This contrasts with constraining to the qualitatively different Kato-cusp-condition densities. The single parameter in the new functional is calibrated by satisfying Pauli potential positivity constraints for pseudo-atom densities. In static lattice tests on simple metals and semiconductors, the new LKT functional outperforms the previous best constraint-based GGA functional, VT84F (Phys.\ Rev.\ B \textbf{88}, 161108(R) (2013)), is generally superior to a recently proposed meta-GGA, is reasonably competitive with parametrized two-point functionals, and is substantially faster.
Kai Luo - One of the best experts on this subject based on the ideXlab platform.
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towards accurate orbital free simulations a Generalized Gradient Approximation for the noninteracting free energy density functional
Physical Review B, 2020Co-Authors: Kai LuoAbstract:For orbital-free {\it ab initio} molecular dynamics, especially on systems in extreme thermodynamic conditions, we provide the first pseudo-potential-adapted Generalized Gradient Approximation (GGA) functional for the non-interacting free energy. This is achieved by systematic finite-temperature extension of our recent LKT ground state non-interacting kinetic energy GGA functional (Phys. Rev. B \textbf{98}, 041111(R) (2018)). We test the performance of the new functional first via static lattice calculations on crystalline aluminum and silicon. Then we compare deuterium equation of state results against both path-integral Monte Carlo and conventional (orbital-dependent) Kohn-Sham results. The new functional, denoted LKTF, outperforms the previous best semi-local free energy functional, VT84F (Phys.\ Rev.\ B \textbf{88}, 161108(R) (2013)), and provides modestly faster simulations. We also discuss subtleties of identification of kinetic and entropic contributions to non-interacting free-energy functionals obtained by extension from ground state orbital-free kinetic energy functionals.
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a simple Generalized Gradient Approximation for the noninteracting kinetic energy density functional
Physical Review B, 2018Co-Authors: Kai Luo, Valentin V. Karasiev, S. B. TrickeyAbstract:A simple, unconventional, nonempirical, constraint-based orbital-free Generalized Gradient Approximation (GGA) noninteracting kinetic energy density functional is presented along with illustrative applications. The innovation is adaptation of constraint-based construction to the essential properties of pseudodensities from the pseudopotentials that are essential in plane-wave-basis ab initio molecular dynamics. This contrasts with constraining to the qualitatively different Kato-cusp-condition densities. The single parameter in the proposed functional is calibrated by satisfying Pauli potential positivity constraints for pseudoatom densities. In static lattice tests on simple metals and semiconductors, the LKT (for the authors' initials) functional outperforms the previous best constraint-based GGA functional, VT84F [Phys. Rev. B 88, 161108(R) (2013)], is generally superior to a recently proposed meta-GGA, is reasonably competitive with parametrized two-point functionals, and is substantially faster.
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a simple Generalized Gradient Approximation for the noninteracting kinetic energy density functional
Physical Review B, 2018Co-Authors: Kai Luo, Valentin V. Karasiev, S. B. TrickeyAbstract:A simple, novel, non-empirical, constraint-based orbital-free Generalized Gradient Approximation (GGA) non-interacting kinetic energy density functional is presented along with illustrative applications. The innovation is adaptation of constraint-based construction to the essential properties of pseudo-densities from the pseudo-potentials that are essential in plane-wave-basis {\it ab initio} molecular dynamics. This contrasts with constraining to the qualitatively different Kato-cusp-condition densities. The single parameter in the new functional is calibrated by satisfying Pauli potential positivity constraints for pseudo-atom densities. In static lattice tests on simple metals and semiconductors, the new LKT functional outperforms the previous best constraint-based GGA functional, VT84F (Phys.\ Rev.\ B \textbf{88}, 161108(R) (2013)), is generally superior to a recently proposed meta-GGA, is reasonably competitive with parametrized two-point functionals, and is substantially faster.
Gustavo E. Scuseria - One of the best experts on this subject based on the ideXlab platform.
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Generalized Gradient Approximation model exchange holes for range separated hybrids
Journal of Chemical Physics, 2008Co-Authors: Thomas M Henderson, Benjamin G Janesko, Gustavo E. ScuseriaAbstract:We propose a general model for the spherically averaged exchange hole corresponding to a Generalized Gradient Approximation (GGA) exchange functional. Parameters are reported for several common GGAs. Our model is based upon that of Ernzerhof and Perdew [J. Chem. Phys. 109, 3313 (1998)]. It improves upon the former by precisely reproducing the energy of the parent GGA, and by enabling fully analytic evaluation of range-separated hybrid density functionals. Analytic results and preliminary thermochemical tests indicate that our model also improves upon the simple, local-density-based exchange hole model of Iikura et al. [J. Chem. Phys. 115, 3540 (2001)].
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restoring the density Gradient expansion for exchange in solids and surfaces
Physical Review Letters, 2008Co-Authors: John P Perdew, Gustavo E. Scuseria, Adrienn Ruzsinszky, Gabor I Csonka, Oleg A Vydrov, Lucian A Constantin, Xiaolan Zhou, Kieron BurkeAbstract:Popular modern Generalized Gradient Approximations are biased toward the description of free-atom energies. Restoration of the first-principles Gradient expansion for exchange over a wide range of density Gradients eliminates this bias. We introduce a revised Perdew-Burke-Ernzerhof Generalized Gradient Approximation that improves equilibrium properties of densely packed solids and their surfaces.
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meta Generalized Gradient Approximation explanation of a realistic nonempirical density functional
Journal of Chemical Physics, 2004Co-Authors: John P Perdew, Jianmin Tao, Viktor N Staroverov, Gustavo E. ScuseriaAbstract:Tao, Perdew, Staroverov, and Scuseria (TPSS) have constructed a nonempirical meta-Generalized Gradient Approximation (meta-GGA) [Phys. Rev. Lett. 91, 146401 (2003)] for the exchange-correlation energy, imposing exact constraints relevant to the paradigm densities of condensed matter physics and quantum chemistry. Results of their extensive tests on molecules, solids, and solid surfaces are encouraging, suggesting that this density functional achieves uniform accuracy for diverse properties and systems. In the present work, this functional is explained and details of its construction are presented. In particular, the functional is constructed to yield accurate energies under uniform coordinate scaling to the low-density or strong-interaction limit. Its nonlocality is displayed by plotting the factor Fxc that gives the enhancement relative to the local density Approximation for exchange. We also discuss an apparently harmless order-of-limits problem in the meta-GGA. The performance of this functional is inv...
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climbing the density functional ladder nonempirical meta Generalized Gradient Approximation designed for molecules and solids
Physical Review Letters, 2003Co-Authors: Jianmin Tao, John P Perdew, Viktor N Staroverov, Gustavo E. ScuseriaAbstract:The electron density, its Gradient, and the Kohn-Sham orbital kinetic energy density are the local ingredients of a meta-Generalized Gradient Approximation (meta-GGA). We construct a meta-GGA density functional for the exchange-correlation energy that satisfies exact constraints without empirical parameters. The exchange and correlation terms respect two paradigms: one- or two-electron densities and slowly varying densities, and so describe both molecules and solids with high accuracy, as shown by extensive numerical tests. This functional completes the third rung of "Jacob's ladder" of Approximations, above the local spin density and GGA rungs.
Jianwei Sun - One of the best experts on this subject based on the ideXlab platform.
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accurate and numerically efficient r 2 scan meta Generalized Gradient Approximation
Bulletin of the American Physical Society, 2021Co-Authors: James W Furness, John P Perdew, Aaron D Kaplan, Jinliang Ning, Jianwei SunAbstract:The recently proposed rSCAN functional [J. Chem. Phys. 150, 161101 (2019)] is a regularized form of the SCAN functional [Phys. Rev. Lett. 115, 036402 (2015)] that improves SCAN's numerical performance at the expense of breaking constraints known from the exact exchange-correlation functional. We construct a new meta-Generalized Gradient Approximation by restoring exact constraint adherence to rSCAN. The resulting functional maintains rSCAN's numerical performance while restoring the transferable accuracy of SCAN.
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accurate and numerically efficient r2scan meta Generalized Gradient Approximation
Journal of Physical Chemistry Letters, 2020Co-Authors: James W Furness, John P Perdew, Aaron D Kaplan, Jinliang Ning, Jianwei SunAbstract:The recently proposed rSCAN functional [ J. Chem. Phys. 2019 150, 161101] is a regularized form of the SCAN functional [ Phys. Rev. Lett. 2015 115, 036402] that improves SCAN’s numerical performanc...
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versatile van der waals density functional based on a meta Generalized Gradient Approximation
Physical Review X, 2016Co-Authors: Haowei Peng, John P Perdew, Zenghui Yang, Jianwei SunAbstract:Van der Waals interactions are ubiquitous in different materials yet not always described properly by current theories. Now, researchers have determined how to accurately and efficiently treat long-range Van der Waals interactions together with other chemical bonds, new findings that are important for studies of layered materials.
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communication effect of the orbital overlap dependence in the meta Generalized Gradient Approximation
Journal of Chemical Physics, 2012Co-Authors: Jianwei Sun, Bing Xiao, Adrienn RuzsinszkyAbstract:We study for the first time the effect of the dependence of meta Generalized Gradient Approximation (MGGA) for the exchange-correlation energy on its input, the kinetic energy density, through the dimensionless inhomogeneity parameter, α, that characterizes the extent of orbital overlap. This leads to a simple MGGA exchange functional, which interpolates between the single-orbital regime, where α = 0, and the slowly varying density regime, where α ≈ 1, and then extrapolates to α → ∞. When combined with a variant of the Perdew-Burke-Ernzerhof GGA correlation, the resulting MGGA performs equally well for atoms, molecules, surfaces, and solids.
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effect of the orbital overlap dependence in the meta Generalized Gradient Approximation
arXiv: Chemical Physics, 2012Co-Authors: Jianwei Sun, Bing Xiao, Adrienn RuzsinszkyAbstract:The dimensionless inhomogeneity parameter, $\alpha$, characterizing the extent of orbital overlap, is disentangled for the first time, by the means of separability assumption, from the other dimensionless inhomogeneity parameter, s, the reduced density Gradient,in the construction of a meta Generalized Gradient Approximation (MGGA) for the exchange functional. We show that the formation of the intershell region between the outermost core and the valence of an atom within a solid is associated with an increase of $\alpha$ and a decrease of $s$. This observation leads to a simple MGGA exchange functional, which interpolates between the single-orbital regime, where $\alpha=0$, and the slowly varying density regime, where $\alpha \approx 1$, and then extrapolates to $\alpha \to \infty$. The exchange enhancement factor penalizes the formation of the intershell region by increasing monotonically with $s$ and decreasing monotonically with $\alpha$. When combined with a variant of the Perdew-Burke-Erzerhof (PBE) GGA correlation, the resulting MGGA performs equally well for atoms, molecules, surfaces, and solids, and respects a tight Lieb-Oxford bound.