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Ferromagnetism on an atom-thick & extended 2D metal-organic coordination network.

ABSTRACT: Ferromagnetism is the collective alignment of atomic spins that retain a net magnetic moment below the Curie temperature, even in the absence of external magnetic fields. Reducing this fundamental property into strictly two-dimensions was proposed in metal-organic coordination networks, but thus far has eluded experimental realization. In this work, we demonstrate that extended, cooperative ferromagnetism is feasible in an atomically thin two-dimensional metal-organic coordination network, despite only ≈ 5% of the monolayer being composed of Fe atoms. The resulting ferromagnetic state exhibits an out-of-plane easy-axis square-like hysteresis loop with large coercive fields over 2 Tesla, significant magnetic anisotropy, and persists up to T_C ≈ 35 K. These properties are driven by exchange interactions mainly mediated by the molecular linkers. Our findings resolve a two decade search for ferromagnetism in two-dimensional metal-organic coordination networks.

SUBMITTER: Lobo-Checa J

PROVIDER: S-EPMC10904770 | biostudies-literature | 2024 Feb

REPOSITORIES: biostudies-literature

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Ferromagnetism on an atom-thick & extended 2D metal-organic coordination network.

Lobo-Checa Jorge J Hernández-López Leyre L Otrokov Mikhail M MM Piquero-Zulaica Ignacio I Candia Adriana E AE Gargiani Pierluigi P Serrate David D Delgado Fernando F Valvidares Manuel M Cerdá Jorge J Arnau Andrés A Bartolomé Fernando F

Nature communications 20240229 1

Ferromagnetism is the collective alignment of atomic spins that retain a net magnetic moment below the Curie temperature, even in the absence of external magnetic fields. Reducing this fundamental property into strictly two-dimensions was proposed in metal-organic coordination networks, but thus far has eluded experimental realization. In this work, we demonstrate that extended, cooperative ferromagnetism is feasible in an atomically thin two-dimensional metal-organic coordination network, despi ...[more]

PMID: 38424075

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Ferromagnetism on an atom-thick & extended 2D metal-organic coordination network.

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Ferromagnetism on an atom-thick & extended 2D metal-organic coordination network.

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