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arXiv · 1010.1319

Effect of ligand substitution on the exchange interactions in {Mn12}-type single-molecule magnets

D. W. Boukhvalov·V. V. Dobrovitski·P. Kögerler·M. Al-Saqer·M. I. Katsnelson·A. I. Lichtenstein·B. N. Harmon
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Abstract

We investigate how the ligand substitution affects the intra-molecular spin exchange interactions, studying a prototypal family of single-molecule magnets comprising dodecanuclear cluster molecules [Mn12O12(COOR)16]. We identify a simple scheme based on accumulated Pauling electronegativity numbers (a.e.n.) of the carboxylate ligand groups (R). The redistribution of the electron density, controlled by a.e.n. of a ligand, changes the degree of hybridization between 3d electrons of manganese and 2p electrons of oxygen atoms, thus changing the exchange interactions. This scheme, despite its conceptual simplicity, provides a strong correlation with the exchange energies associated with carboxylate bridges, and is confirmed by the electronic structure calculations taking into account the Coulomb correlations in magnetic molecules.

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D. W. Boukhvalov, V. V. Dobrovitski, P. Kögerler, M. Al-Saqer, M. I. Katsnelson, A. I. Lichtenstein, B. N. Harmon. 2010-10-07. Effect of ligand substitution on the exchange interactions in {Mn12}-type single-molecule magnets. https://arxiv.org/abs/1010.1319

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