Logo RUB
  • Institute
    • ICAMS
      • Mission
      • Structure
      • Members
      • Fellows
    • Departments & Research Groups
      • Atomistic Modelling and Simulation
      • Scale-Bridging Thermodynamic and Kinetic Simulation
      • Micromechanical and Macroscopic Modelling
      • Artificial Intelligence for Integrated Material Science
      • Computational Design of Functional Interfaces
      • Scale-Bridging Simulation of Functional Composites
      • Materials Informatics and Data Science
      • High-Performance Computing in Materials Science
    • Central Services
      • Coordination Office
      • IT
  • Research
    • Overview
    • Publications
    • Software and Data
    • Collaborative research
    • Research networks
    • Young enterprises
  • Teaching
    • Overview
    • Materialwissenschaft B.Sc.
    • Materials Science and Simulation M.Sc.
    • ICAMS Graduate School
    • Student Projects
  • News & Events
    • Overview
    • News
    • Seminars and Workshops
    • Conferences
  • Services
    • Overview
    • Contact
    • Open positions
    • Travel information
 
ICAMS
ICAMS
MENÜ
  • RUB-STARTSEITE
  • Institute
    • ICAMS
    • Departments & Research Groups
    • Central Services
  • Research
    • Overview
    • Publications
    • Software and Data
    • Collaborative research
    • Research networks
    • Young enterprises
  • Teaching
    • Overview
    • Materialwissenschaft B.Sc.
    • Materials Science and Simulation M.Sc.
    • ICAMS Graduate School
    • Student Projects
  • News & Events
    • Overview
    • News
    • Seminars and Workshops
    • Conferences
  • Services
    • Overview
    • Contact
    • Open positions
    • Travel information

Just another WordPress site - Ruhr-Universität Bochum

Meta-local density functionals: a new rung on Jacob’s ladder

S. Lehtola, M. Marques

Journal of Chemical Theory and Computation, 17, 943–948, (2021)

DOI: 10.1021/acs.jctc.0c01147

Download: BibTEX

The homogeneous electron gas (HEG) is a key ingredient in the construction of most exchange-correlation functionals of density-functional theory. Often, the energy of the HEG is parameterized as a function of its spin density nσ, leading to the local density approximation (LDA) for inhomogeneous systems. However, the connection between the electron density and kinetic energy density of the HEG can be used to generalize the LDA by evaluating it on a geometric average nσavg(r) = nσ1–x(r)ñσx(r) of the local spin density nσ(r) and the spin density ñσ(r) of a HEG that has the local kinetic energy density τσ(r) of the inhomogeneous system. This leads to a new family of functionals that we term meta-local density approximations (meta-LDAs), which are still exact for the HEG, which are derived only from properties of the HEG and which form a new rung of Jacob’s ladder of density functionals [ AIP Conf. Proc. 2001, 577, 1]. The first functional of this ladder, the local τ approximation (LTA) of Ernzerhof and Scuseria [ J. Chem. Phys. 1999, 111, 911] that corresponds to x = 1 is unfortunately not stable enough to be used in self-consistent field calculations because it leads to divergent potentials, as we show in this work. However, a geometric averaging of the LDA and LTA densities with smaller values of x not only leads to numerical stability of the resulting functional but also yields more accurate exchange energies in atomic calculations than the LDA, the LTA, or the tLDA functional (x = 1/4) of Eich and Hellgren [ J. Chem. Phys. 2014, 141, 224107]. We choose x = 0.50, as it gives the best total energy in self-consistent exchange-only calculations for the argon atom. Atomization energy benchmarks confirm that the choice x = 0.50 also yields improved energetics in combination with correlation functionals in molecules, almost eliminating the well-known overbinding of the LDA and reducing its error by two thirds.

back
{"type":"article", "name":"s.lehtola20212", "author":"S. Lehtola and M. Marques", "title":"Metalocal density functionals: a new rung on Jacob’s ladder", "journal":"Journal of Chemical Theory and Computation", "volume":"17", "OPTnumber":"2", "OPTmonth":"2", "year":"2021", "OPTpages":"943–948", "OPTnote":"", "OPTkey":"chemical calculations; electrical properties; electron density; energy; energy density", "DOI":"10.1021/acs.jctc.0c01147"}
Logo RUB
  • Open positions
  • Travel information
  • Imprint
  • Privacy Policy
  • Sitemap
Ruhr-Universität Bochum
Universitätsstraße 150
44801 Bochum

  • Open positions
  • Travel information
  • Imprint
  • Privacy Policy
  • Sitemap
Seitenanfang Kontrast N