Abstract
Quantum-chemical “descriptors”, including atomic partial charges,
orbitals, and electrostatic potentials are powerful tools for
understanding chemical reactivity. Localized defects in graphene are a
particular challenge for these tools, especially to model the adsorption
processes and to predict the interactions of transition metals with
these defects. Such defects often have little charge polarization and a
combination of localized and delocalized states. Our orbital overlap
distance D(r) measures the “size” of occupied orbital lobes
about point r, distinguishing the hybridization state and
compact vs. diffuse character of local electronic structure. Here
we apply the overlap distance to graphene defects. We find that the
overlap distance clearly distinguishes differential reactivities of
different atoms at intrinsic defects. Combining the overlap distance and
electrostatic potential provides a rich picture of extrinsic defect
reactivity, including semiquantitative predictions of transition metal
binding.