Helium

helium

name helium
formula He
CAS number 7440-59-7

Dielectric screening

Eigenvalues of the symmetrized irreducible polarizability for helium, He, computed in WEST by iterative diagonalization, using the PBE functional.

helium

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Spectral function

The G0W0 HOMO spectral function of helium, He, computed in WEST with full frequency integration, using the PBE functional.

helium

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Vertical ionization potential (G0W0@PBE)

software basis set extrapolation core electrons self-energy QP eq. solver VIP [eV] ref.
FHI-aims LO yes AE AC Full 23.49 [1]
VASP PW yes PSP AC Linear 23.62 [2]
VASP PW yes PSP AC Full 23.38 [2]
WEST PW yes PSP FF-CD Linear 23.648 [3]
WEST PW yes PSP FF-CD Full 23.417 [3]
EXP 24.59 [4]

Vertical electron affinity (G0W0@PBE)

software basis set extrapolation core electrons self-energy QP eq. solver VEA [eV] ref.
WEST PW yes PSP FF-CD Linear -0.017 [3]
WEST PW yes PSP FF-CD Full -0.017 [3]

Legend

  • AE: All electron
  • AC: Analytic continuation
  • EXP: Experimental value, if marked in parentheses the ionization potential is not vertical
  • FF-CD: Full frequency integration with contour deformation
  • FF-RA: Full frequency integration along the real axis
  • Full: Full solution of the quasiparticle (QP) equation
  • Linear: Solution of the linearized quasiparticle (QP) equation
  • LO: Localized orbitals
  • PSP: Pseudopotential
  • PW: Plane waves

References

  1. GW100: Benchmarking G0W0 for Molecular Systems, M.J. van Setten et al., J. Chem. Theory Comput. 11, 5665 (2015).
  2. GW100: A Plane Wave Perspective for Small Molecules, E. Maggio et al., J. Chem. Theory Comput. 13, 635 (2017).
  3. GW100: Comparison of Methods and Accuracy of Results Obtained with the WEST Code, M. Govoni, and G. Galli, J. Chem. Theory Comput. 18, 1895 (2018).
  4. P.J. Linstrom and W.G. Mallard, Eds., NIST Chemistry WebBook, NIST Standard Reference Database Number 69, National Institute of Standards and Technology, Gaithersburg MD, 20899.