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ORIGINAL PAPER

Structural and Magnetic Properties of CrN: Investigated by First-Principles Calculations, Monte Carlo Simulation, and High-Temperature Series Expansions A. Azouaoui1

· N. Benzakour1 · A. Hourmatallah2 · K. Bouslykhane1

Received: 12 March 2020 / Accepted: 27 May 2020 © Springer Science+Business Media, LLC, part of Springer Nature 2020

Abstract We have employed first-principles calculations of density functional theory (DFT) with GGA and GGA+U exchange correlation to study structural, magnetic, and electronic properties of chromium nitride (CrN) in the rock salt (NaCl) structures. The obtained data from DFT calculations is used as an input in high-temperature series expansions (HTSEs) combined with the Pad´e approximants (PA) method and Monte Carlo simulation (MC) for the Ising model to investigate the magnetic properties of CrN. The obtained results show that CrN is more stable in the antiferromagnetic order, and undergoes structural and magnetic transitions from an antiferromagnetic NaCl structure to a nonmagnetic Pnma phase at 201 GPa. The density of states (DOS) with GGA approach shows that CrN has a metallic behavior in both FM and AFM configurations whereas with GGA+U CrN is semiconductor in AFM and half-metallic in FM order. The Neel temperature (TN ) obtained by HTSE and MC is in agreement with available experimental data. Keywords DFT · Pressure · Half-metallic · Monte Carlo simulation · Critical temperature

1 Introduction Transition metal mononitrides (TMNs) are considered a class of technologically important materials and have been a great interest in recent years for their promising properties, such as high hardness [1], high mechanical resistance, high melting point, and high temperature stability[2]. These properties make TMNs attractive in many applications such as diffusion barriers, hard protective coatings on cutting tools, and wear-resistant electrical contacts. TMNs take on various crystal structures as cubic zincblende, rock salt (NaCl), cesium chloride, NiAs, and WC. To predict the mechanical stability of TMN compounds and their  A. Azouaoui

[email protected] 1

Laboratoire de Physique du Solide, Universit´e Sidi Mohammed Ben Abdellah, Facult´e des sciences Dhar Mahraz, BP 1796, Fes, Morocco

2

Laboratoire LIPI, Equipe de Physique du Solide, Universit´e Sidi Mohammed Ben Abdellah Ecole Normale Sup´erieure, BP 5206, Bensouda, Fes, Morocco

properties, many theoretical studies have been carried out on transition metals, based on the calculation of functional density [3–5]. Widely varying results of the structural properties found show that the structural properties of transition metal mononitrides are highly dependent on the theoretical model used. Most of transition metal nitrides are known to have a rock salt (NaCl) structure or zincblende (ZB) structure. The NaCl structure has attracted considerable interest such as a large range of room temperature resistance ρ [6]. Among these transition metal mononitrides, chromium nitride (CrN) is widely applicability in the industr