Eur. Phys. J. B (2021) 94: 214
https://doi.org/10.1140/epjb/s10051-021-00225-5

Regular Article - Solid State and Materials

Theoretical study of the magnetic properties of BaNiF${}_4$

¹ Centre Interdisciplinaire de Nanoscience de Marseille-CNRS (UMR 7325), Aix-Marseille University, Marseille, France
² Institut Néel, CNRS-UPR 2940, BP 166, 25 av. des Martyrs, 38042, Grenoble Cedex 9, France
³ Institut Laue Langevin, 71 av. des Martyrs, CS 20156, 38042, Grenoble Cedex 9, France

^c saul@cinam.univ-mrs.fr

Received: 28 July 2021
Accepted: 7 October 2021
Published online: 25 October 2021

Abstract

In this article we study the magnetic properties of the BaNiF${}_4$ compound using ab-initio calculations and classical Monte-Carlo methods. We discuss the physical origin of the long range magnetic order. We show that the leading exchange interactions are those of a non-frustrated anisotropic two-dimensional Heisenberg system and that long range order and the experimentally observed preferential orientation of the magnetic moments along the $\mathbf{b}$ axis appear when local single-ion anisotropy contributions are added at first order. We also show that a canting of the magnetic moments appears at second order and can be written as an effective Dzyaloshinskii-Moriya interaction.