Anisotropic potential energy functions for carbon atoms in graphite

Recent experimental studies of the scattering of He atomic beams by graphite have shown that the electronic anisotropy of the C atoms must be taken into account in calculating the interaction between a graphite lattice and an external He atom. The empirical compressibility of graphite is used to determine an appropriate value for the polarizability of graphite C atoms parallel to the graphite c axis, a parameter needed to calculate He-graphite interaction potentials.