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arXiv · 1302.3023

Ligand field parameters and the ground state of Fe(II) phthalocyanine

M. D. Kuz'min·A. Savoyant·R. Hayn
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Abstract

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 $a_{1g}^2 e_g^{\uparrow\downarrow\uparrow} b_{2g}^{\uparrow}$ ($^3E_g$). The ligand field parameters, in relation to Racah's $C$, 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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M. D. Kuz'min, A. Savoyant, R. Hayn. 2013-02-13. Ligand field parameters and the ground state of Fe(II) phthalocyanine. https://doi.org/10.1063/1.4811110

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