TY - JOUR
T1 - Polarization-induced renormalization of molecular levels at metallic and semiconducting surfaces
AU - García Lastra, Juan Maria
AU - Rostgaard, Carsten
AU - Rubio, A.
AU - Thygesen, Kristian Sommer
N1 - Copyright 2009 American Physical Society
PY - 2009
Y1 - 2009
N2 - On the basis of first-principles G0W0 calculations we systematically study how the electronic levels of a benzene molecule are renormalized by substrate polarization when physisorbed on different metallic and semiconducting surfaces. The polarization-induced reduction in the energy gap between occupied and unoccupied molecular levels is found to scale with the substrate density of states at the Fermi level (for metals) and substrate band gap (for semiconductors). These conclusions are further supported by self-consistent GW calculations on simple lattice models. By expressing the electron self-energy in terms of the substrate’s joint density of states we relate the level shift to the surface electronic structure, thus providing a microscopic explanation of the trends in the GW and G0W0 calculations. While image charge effects are not captured by semilocal and hybrid exchange-correlation functionals, we find that error cancellations lead to remarkably good agreement between the G0W0 and Kohn-Sham energies for the occupied orbitals of the adsorbed molecule.
AB - On the basis of first-principles G0W0 calculations we systematically study how the electronic levels of a benzene molecule are renormalized by substrate polarization when physisorbed on different metallic and semiconducting surfaces. The polarization-induced reduction in the energy gap between occupied and unoccupied molecular levels is found to scale with the substrate density of states at the Fermi level (for metals) and substrate band gap (for semiconductors). These conclusions are further supported by self-consistent GW calculations on simple lattice models. By expressing the electron self-energy in terms of the substrate’s joint density of states we relate the level shift to the surface electronic structure, thus providing a microscopic explanation of the trends in the GW and G0W0 calculations. While image charge effects are not captured by semilocal and hybrid exchange-correlation functionals, we find that error cancellations lead to remarkably good agreement between the G0W0 and Kohn-Sham energies for the occupied orbitals of the adsorbed molecule.
U2 - 10.1103/PhysRevB.80.245427
DO - 10.1103/PhysRevB.80.245427
M3 - Journal article
SN - 0163-1829
VL - 80
SP - 245427
JO - Physical Review B Condensed Matter
JF - Physical Review B Condensed Matter
IS - 24
ER -