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arXiv · 1811.00867

Ferromagnetic ordering of linearly coordinated Co ions in LiSr$_2$[CoN$_2$]

T. J. Ballé·Z. Zangeneh·L. Hozoi·A. Jesche·P. Höhn
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Abstract

LiSr$_2$[CoN$_2$] single crystals were successfully grown out of Li-rich flux. Temperature- and field-dependent measurements of the magnetization in the range of $T = 2 - 300$ K and up to $μ_{0}\textit{H} = 7$ T as well as measurements of the heat capacity are presented. Ferromagnetic ordering emerges below $T_C = 44$ K and comparatively large coercivity fields of $μ_0H = 0.3$ T as well as pronounced anisotropy are observed upon cooling. Polycrystalline samples of the Ca analog LiCa$_2$[CoN$_2$] were obtained and investigated in a similar way. In both compounds Co manifests orbital contributions to the magnetic moment and large single-ion anisotropy that is caused by second-order Spin-orbit coupling. Quantum chemistry calculations reveal a magnetic anisotropy energy of 7 meV, twice as large as the values reported for similar Co $d^{8}$ systems.

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T. J. Ballé, Z. Zangeneh, L. Hozoi, A. Jesche, P. Höhn. 2018-11-02. Ferromagnetic ordering of linearly coordinated Co ions in LiSr$_2$[CoN$_2$]. https://doi.org/10.1103/physrevb.99.094422

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