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Strong Exchange Couplings Drastically Slow Down Magnetization Relaxation in an Air-Stable Cobalt(II)-Radical Single-Molecule Magnet (SMM).

ABSTRACT: The energy barrier leading to magnetic bistability in molecular clusters is determined by the magnetic anisotropy of the cluster constituents. By incorporating a highly anisotropic four-coordinate cobalt(II) building block into a strongly coupled fully air- and moisture-stable three-spin system, it proved possible to suppress under-barrier Raman processes leading to 350-fold increase of magnetization relaxation time and pronounced hysteresis. Relaxation times of up to 9 hours at low temperatures were found.

SUBMITTER: Albold U

PROVIDER: S-EPMC6771987 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Strong Exchange Couplings Drastically Slow Down Magnetization Relaxation in an Air-Stable Cobalt(II)-Radical Single-Molecule Magnet (SMM).

Albold Uta U Bamberger Heiko H Hallmen Philipp P PP van Slageren Joris J Sarkar Biprajit B

Angewandte Chemie (International ed. in English) 20190606 29

The energy barrier leading to magnetic bistability in molecular clusters is determined by the magnetic anisotropy of the cluster constituents. By incorporating a highly anisotropic four-coordinate cobalt(II) building block into a strongly coupled fully air- and moisture-stable three-spin system, it proved possible to suppress under-barrier Raman processes leading to 350-fold increase of magnetization relaxation time and pronounced hysteresis. Relaxation times of up to 9 hours at low temperatures ...[more]

PMID: 31050153

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