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arXiv · 1809.04809

Incipient spin-dipole coupling in a 1D helical-chain metal-organic hybrid

Abstract

Low dimensional magnetic systems (such as spin-chain) are extensively studied due to their exotic magnetic properties. Here, we would like to address that such systems should also be interesting in the field of dielectric, ferroelectricity and magnetodielectric coupling. As a prototype example, we have investigated a one-dimensional (1D) helical-chain metal-organic hybrid system with a chiral structure which shows a broad hump in magnetic susceptibility around 55 K (Tmax). The complex dielectric constant exactly traces this feature, which suggests intrinsic magnetodielectric coupling in this chiral system. The dipolar ordering at Tmax occurs due to lattice-distortion which helps to minimize the magnetic energy accompanied by 1D-magnetic ordering or vice-versa. This experimental demonstration initiates a step to design and investigate hybrid organic-inorganic magnetic systems consisting of chiral structure towards ferroelectricity and magnetodielectric coupling.

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Tathamay Basu, Clarisse Bloyet, Jean-Michel Rueff, Vincent Caignaert, Alain Pautrat, Bernard Raveau, Guillaume Rogez, Paul-Alain Jaffrès. 2018-09-13. Incipient spin-dipole coupling in a 1D helical-chain metal-organic hybrid. https://doi.org/10.1039/c8tc04328k

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