A judicious analysis of previously published experimental data leads one to conclude that the ground state of iron(II) phthalocyanine is an orbitally degenerate spin triplet $a_{1g}^2 e_g^{uparrowdownarrowuparrow} b_{2g}^{uparrow}$ ($^3E_g$). The ligand field parameters, in relation to Racahs $C$, are approximately as follows: $B_{20}/C=0.84$, $B_{40}/C=0.0074$. The uniqueness of this result is demonstrated by means of a special diagram in the $B_{20}/C-B_{40}/C$ plane (under additional conditions that $B_{44}/B_{40}=35/3$ and $B/C=0.227$). The system is in a strong-ligand-field regime, which enables the use of single-determinant techniques corrected for correlations within the 3d shell of Fe.
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