  We calculate the angular dependence of the x-ray linear and circular
dichroism at the $L_{2,3}$ edges of $\alpha$-Fe(II) Phthalocyanine (FePc) thin
films using a ligand field model with full configuration interaction. We find
the best agreement with the experimental spectra for a mixed ground state of
$^3E_{g}(a_{1g}^2e_g^3b_{2g}^1)$ and $^3B_{2g}(a_{1g}^1e_g^4b_{2g}^1)$ with the
two configurations coupled by the spin-orbit interaction. The $^3E_{g}(b)$ and
$^3B_{2g}$ states have an easy axis and plane anisotropies, respectively. Our
model accounts for an easy-plane magnetic anisotropy and the measured
magnitudes of the in-plane orbital and spin moments. The proximity in energy of
the two configurations allows a switching of the magnetic anisotropy from easy
plane to easy axis with a small change in the crystal field, as recently
observed for FePc adsorbed on an oxidized Cu surface. We also discuss the
possibility of a quintet ground state ($^5A_{1g}$ is 250~meV above the ground
state) with planar anisotropy by manipulation of the Fe-C bond length by
depositing the complex on a substrate that is subjected to a mechanical strain.
