  A localized description, rather than energy bands, is appropriate for the
manganite substrate. Empty substrate levels lower in energy than occupied
oxygen levels indicate need for further terms beyond the Local Density
Approximation. So also does van-der-Waals interaction between the two. Methods
to include both are suggested by related, exactly soluble, two-electron
problems. The descriptions of the electronic structure of the molecule and a
LaSrMnO3 (LSM) substrate are greatly simplified to allow incorporation of these
effects and to treat a range of problems involving the interactions between
oxygen atoms, or oxygen molecules, and such a substrate. These include elastic
impacts, impacts with electronic transitions, and impacts with phonon
excitation. They provide for capture of the atoms or molecules by the surface,
leaving the neutral molecule strongly bound over a Mn(4+) site. It is found
that oxygen vacancies in LSM diffuse as a neutral species, and can appear at
the surface. Bound molecules tend to avoid sites next to vacancies but, if
there, should drop one atom into the vacancy leaving the remaining triplet
oxygen atom bound to the resulting ideal surface, with no need for spin flips
nor successive ionization steps.
