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Switchable Multiple Spin States in the Kondo description of Doped Molecular Magnets.

ABSTRACT: We show that introducing electrons in magnetic clusters and molecular magnets lead to rich phase diagrams with a variety of low-spin and high-spin states allowing for multiple switchability. The analysis is carried out for a quantum spin-fermion model using the exact diagonalization, and the cluster mean-field approach. The model is relevant for a number of molecular magnets with triangular motifs consisting of transition metal ions such as Cr, Cu and V. Re-entrant spin-state behavior and chirality on-off transitions exist over a wide parameter regime. A subtle competition among geometrical frustration effects, electron itinerancy, and Kondo coupling at the molecular level is highlighted. Our results demonstrate that electron doping provides a viable mean to tame the magnetic properties of molecular magnets towards potential technological applications.

SUBMITTER: Ray R

PROVIDER: S-EPMC5296747 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Switchable Multiple Spin States in the Kondo description of Doped Molecular Magnets.

Ray Rajyavardhan R Kumar Sanjeev S

Scientific reports 20170208

We show that introducing electrons in magnetic clusters and molecular magnets lead to rich phase diagrams with a variety of low-spin and high-spin states allowing for multiple switchability. The analysis is carried out for a quantum spin-fermion model using the exact diagonalization, and the cluster mean-field approach. The model is relevant for a number of molecular magnets with triangular motifs consisting of transition metal ions such as Cr, Cu and V. Re-entrant spin-state behavior and chiral ...[more]

PMID: 28176869

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