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Slow magnetic relaxation in a novel carboxylate/oxalate/hydroxyl bridged dysprosium layer.

ABSTRACT: A new 2D dysprosium layer compound has been successfully synthesized from reaction with 2-(3-pyridyl) pyrimidine-4-carboxylic acid (H3-py-4-pmc), in which the Dy³⁺ ions reside in square antiprismatic coordination environments and are connected by carboxylate/oxalate/hydroxyl bridges. Magnetic studies reveal ferromagnetic interactions between Dy³⁺ ions, slow magnetic relaxation with an effective energy barrier U_eff of 186 K under zero dc field and pronounced hysteresis loops at low temperatures. Further dilution magnetic study suggests that the slow magnetic relaxation originates from the single-ion magnetic behavior of Dy³⁺ ion and that magnetic coupling suppresses the quantum tunneling of magnetization at low temperature. In addition, theoretical calculation indicates strong Ising anisotropy of the Dy³⁺ ion that is due to the strong interaction between Dy³⁺ ions and hydroxyl groups.

SUBMITTER: Yin DD

PROVIDER: S-EPMC5490050 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Slow magnetic relaxation in a novel carboxylate/oxalate/hydroxyl bridged dysprosium layer.

Yin Dan-Dan DD Chen Qi Q Meng Yin-Shan YS Sun Hao-Ling HL Zhang Yi-Quan YQ Gao Song S

Chemical science 20150317 5

A new 2D dysprosium layer compound has been successfully synthesized from reaction with 2-(3-pyridyl) pyrimidine-4-carboxylic acid (H3-py-4-pmc), in which the Dy3+ ions reside in square antiprismatic coordination environments and are connected by carboxylate/oxalate/hydroxyl bridges. Magnetic studies reveal ferromagnetic interactions between Dy3+ ions, slow magnetic relaxation with an effective energy barrier Ueff of 186 K under zero dc field and pronounce ...[more]

PMID: 28706683

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