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arXiv · 1804.01551

Heterobimetallic Dy-Cu coordination compound as a classical-quantum ferrimagnetic chain of regularly alternating Ising and Heisenberg spins

J. Torrico·J. Strecka·M. Hagiwara·O. Rojas·S. M. de Souza·Y. Han·Z. Honda·M. L. Lyra
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Abstract

A classical-quantum chain composed of regularly alternating Ising and Heisenberg spins is rigorously solved by considering two distinct local anisotropy axes of the Ising spins. The ground-state phase diagram and magnetization curves are examined depending on a spatial orientation of the applied magnetic field. The phase diagram totally consists of four distinct phases and a few macroscopically degenerate points, where an outstanding coexistence of perfect order and complete disorder occurs within the so-called 'half-fire, half-ice' state. The zero-temperature magnetization curves generally exhibit a smooth dependence on a magnetic field owing to a canting angle between two coplanar anisotropy axes of the Ising spins, which enforces a misalignment of the magnetization vector from a direction of the applied magnetic field. It is evidenced that the investigated spin-chain model reproduces magnetic features of the heterobimetallic coordination compound Dy(NO)$_{3}$(DMSO)$_{2}$Cu(opba)(DMSO)$_{2}$ (DMSO=dimethylsulfoxide, opba=orthophenylenebisoxamato). The high-field magnetization data reported for the powder sample of this polymeric coordination compound generally display a substantial smoothing on account of a powder averaging.

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J. Torrico, J. Strecka, M. Hagiwara, O. Rojas, S. M. de Souza, Y. Han, Z. Honda, M. L. Lyra. 2018-04-04. Heterobimetallic Dy-Cu coordination compound as a classical-quantum ferrimagnetic chain of regularly alternating Ising and Heisenberg spins. https://doi.org/10.1016/j.jmmm.2018.04.021

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