Multiconfiguration Pair-Density Functional Theory for Vertical Excitation Energies in Actinide Molecules

Sarkar, Arup; Gagliardi, Laura

doi:10.1021/acs.jpca.3c05803

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Multiconfiguration Pair-Density Functional Theory for Vertical Excitation Energies in Actinide Molecules

Sarkar, Arup·Gagliardi, Laura

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Abstract

Modeling actinides with electronic structure theories is challenging because these systems present a strong ligand field and metal–ligand covalency. Here, we systematically investigate the effectiveness of pair-density functional theory (PDFT) for the calculation of vertical excitation energies in An(III), [An III Cl 6 ] 3– , and [An VI O 2 ] 2+ (An = U, Np, Pu, and Am). We compare the performance of PDFT, hybrid PDFT, and multistate PDFT with traditional active-space methods followed by perturbation theory, like multistate CASPT2, and with experimental data. Overall, multistate PDFT gives quantitative agreement with multistate CASPT2 at a significantly reduced computational cost.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY MC-PDFT actinides chemical calculations electrical energy ions multireference methods spin-orbit coupling

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Sarkar, Arup, Gagliardi, Laura. 2023-10-27. Multiconfiguration Pair-Density Functional Theory for Vertical Excitation Energies in Actinide Molecules. https://doi.org/10.1021/acs.jpca.3c05803

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