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Complex magnetic structure and magnetocapacitance response in a non-oxide NiF2 system.

ABSTRACT: We report here on the complex magnetic structure and magnetocapacitance in NiF2, a non-oxide multifunctional system. It undergoes an anti-ferromagnetic transition near 68.5?K, superimposed with canted Ni spin driven weak ferromagnetic ordering, followed by a metastable ferromagnetic phase at or below 10?K. Our density functional calculations account for the complex magnetic structure of NiF2 deduced from the temperature and the field dependent measurements. Near room temperature, NiF2 exhibits a relatively large dielectric response reaching >103 with a low dielectric loss of <0.5 at frequencies >20?Hz. This is attributed to the intrinsic grain contribution in contrast to the grain boundary contribution in most of the known dielectric materials. The response time is 10??s or more at 280?K. The activation energy for such temperature dependent relaxation is ~500?meV and is the main source for grain contribution. Further, a large negative magneto capacitance >90% is noticed in 1?T magnetic field. We propose that our findings provide a new non-oxide multifunctional NiF2, useful for dielectric applications.

SUBMITTER: Arumugam S

PROVIDER: S-EPMC6397207 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Complex magnetic structure and magnetocapacitance response in a non-oxide NiF2 system.

Arumugam S S Sivaprakash P P Dixit Ambesh A Chaurasiya Rajneesh R Govindaraj L L Sathiskumar M M Chatterjee Souvik S Suryanarayanan R R

Scientific reports 20190301 1

We report here on the complex magnetic structure and magnetocapacitance in NiF2, a non-oxide multifunctional system. It undergoes an anti-ferromagnetic transition near 68.5 K, superimposed with canted Ni spin driven weak ferromagnetic ordering, followed by a metastable ferromagnetic phase at or below 10 K. Our density functional calculations account for the complex magnetic structure of NiF2 deduced from the temperature and the field dependent measurements. Near room temper ...[more]

PMID: 30824711

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Complex magnetic structure and magnetocapacitance response in a non-oxide NiF2 system.

Publications

Complex magnetic structure and magnetocapacitance response in a non-oxide NiF<sub>2</sub> system.

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