LiSr2[CoN2] 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 μ0H=7 T as well as measurements of the heat capacity are presented. Ferromagnetic ordering emerges below TC=44 K and comparatively large coercivity fields of μ0H=0.3 T as well as pronounced anisotropy are observed upon cooling. Polycrystalline samples of the Ca analog LiCa2[CoN2] 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 d8 systems.
@article{arxiv.1811.00867,
title = {Ferromagnetic ordering of linearly coordinated Co ions in LiSr$_2$[CoN$_2$]},
author = {T. J. Ballé and Z. Zangeneh and L. Hozoi and A. Jesche and P. Höhn},
journal= {arXiv preprint arXiv:1811.00867},
year = {2019}
}