Preferred Label : Koopmans' theorem;
IUPAC definition : Directly relates experimental ionization potentials with energy levels of molecular
orbitals. The theorem states that the ionization potential required to remove an electron
from the orbital Ψ i is given by the negative value of the energy of the orbital,
-εi, as calculated within the Hartree–Fock approximation. The theorem is not applied
to localized molecular orbitals, which are not eigenfunctions of the effective hamiltonian.;
Origin ID : K03411;
See also
Directly relates experimental ionization potentials with energy levels of molecular
orbitals. The theorem states that the ionization potential required to remove an electron
from the orbital Ψ i is given by the negative value of the energy of the orbital,
-εi, as calculated within the Hartree–Fock approximation. The theorem is not applied
to localized molecular orbitals, which are not eigenfunctions of the effective hamiltonian.
