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Updated: May 1, 2026
Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
Crystal fields of porphyrins and phthalocyanines from polarization-dependent 2p-to-3d multiplets
Phillip S Johnson1, J M García-Lastra2, Colton K Kennedy3
1Department of Physics, University of Wisconsin-Madison, 1150 University Ave., Madison, Wisconsin 53706, USA.
Abstract:
Polarization-dependent X-ray absorption spectroscopy is combined with density functional calculations and atomic multiplet calculations to determine the crystal field parameters 10Dq, Ds, and Dt of transition metal phthalocyanines and octaethylporphyrins (Mn, Fe, Co, Ni). The polarization dependence facilitates the assignment of the multiplets in terms of in-plane and out-of-plane orbitals and avoids ambiguities. Crystal field values from density functional calculations provide starting values close to the optimum fit of the data. The resulting systematics of the crystal field can be used for optimizing electron-hole separation in dye-sensitized solar cells.
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