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Spin-Electric Coupling in a Cobalt(II)-Based Spin Triangle Revealed by Electric-Field-Modulated Electron Spin Resonance Spectroscopy.

ABSTRACT: A cobalt(II)-based spin triangle shows a significant spin-electric coupling. [Co₃ (pytag)(py)₆ Cl₃ ]ClO₄ ⋅3 py crystallizes in the acentric monoclinic space group P2₁ . The intra-triangle antiferromagnetic interaction, of the order of ca. -15 cm^-1 (H=-JS_a S_b ), leads to spin frustration. The two expected energy-degenerate ground doublets are, however, separated by a few wavenumbers, as a consequence of magnetic anisotropy and deviations from threefold symmetry. The Co₃ planes of symmetry-related molecules are almost parallel, allowing for the determination of the spin-electric properties of single crystals by EFM-ESR spectroscopy. The spin-electric effect detected when the electric field is applied in the Co₃ plane was revealed by a shift in the resonance field. It was quantified as Δg_E /E=0.11×10^-9 m V^-1 , which in terms of frequency corresponds to approximately 0.3 Hz m V^-1 . This value is comparable to what was determined for a Cu₃ triangle despite the antiferromagnetic interaction being 20 times larger for the latter.

SUBMITTER: Kintzel B

PROVIDER: S-EPMC8048656 | biostudies-literature |

REPOSITORIES: biostudies-literature

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