Computing the Fukui Function in Solid-State Chemistry: Application to Alkaline Earth Oxides Bulk and Surfaces

Fukui functions (FFs)
are chemical descriptors that are useful
to explain the reactivity of systems toward electron transfer. Whereas
they have been widely employed for molecules, their application to
extended systems is scarce. One of the reasons for the limited development
of such analysis in solids is the improper evaluation of FFs in the
usual computational approaches based on density functional theory
and periodic boundary conditions. In this work we compare the available
approaches and propose a new method based on the interpolation of
partially charged systems that mitigates some of the problems encountered.
We discuss the reactivity of alkaline earth oxides (MgO, CaO, SrO,
and BaO) in terms of the FF analysis, providing a robust way to account
for the higher reactivity of surface oxygen sites compared with bulk
sites.