TY - JOUR

T1 - Magnetic moments in CrN-based systems are robust

T2 - An ab initio study of alloys and superlattices

AU - Matas, Martin

AU - Mayrhofer, Paul Heinz

AU - Holec, David

N1 - Publisher Copyright: © 2024 The Author(s)

PY - 2024/11/23

Y1 - 2024/11/23

N2 - CrN belongs to a family of transition metal nitrides used as protective coatings. It has an antiferromagnetic (AFM) orthorhombic structure below the Néel temperature (T N) and adopts paramagnetic (PM) cubic B1 above T N. In the past, the PM state was often wrongly approximated by a non-magnetic (NM) configuration. First-principles calculations suggested interesting mechanical properties of this hypothetical NM-CrN phase. In this work, we use density functional theory to probe the hypothesis that alloying or spatial confinement can cause local quenching of the Cr magnetic moments and, hence, stabilize the NM-CrN phase. Our calculations show that the magnetic moments are extremely robust and remain almost intact irrespective of which of the group III B to group VI B elements is alloyed. Similarly, superlattices with AlN and TiN in various thickness ratios do not reveal any quenching of the local magnetic moments. We therefore conclude that it is unlikely that material design would promote the NM-CrN phase, which thereby remains a purely hypothetical construct.

AB - CrN belongs to a family of transition metal nitrides used as protective coatings. It has an antiferromagnetic (AFM) orthorhombic structure below the Néel temperature (T N) and adopts paramagnetic (PM) cubic B1 above T N. In the past, the PM state was often wrongly approximated by a non-magnetic (NM) configuration. First-principles calculations suggested interesting mechanical properties of this hypothetical NM-CrN phase. In this work, we use density functional theory to probe the hypothesis that alloying or spatial confinement can cause local quenching of the Cr magnetic moments and, hence, stabilize the NM-CrN phase. Our calculations show that the magnetic moments are extremely robust and remain almost intact irrespective of which of the group III B to group VI B elements is alloyed. Similarly, superlattices with AlN and TiN in various thickness ratios do not reveal any quenching of the local magnetic moments. We therefore conclude that it is unlikely that material design would promote the NM-CrN phase, which thereby remains a purely hypothetical construct.

KW - Alloys

KW - CrN

KW - DFT

KW - Magnetism

KW - Superlattices

UR - http://www.scopus.com/inward/record.url?scp=85210289834&partnerID=8YFLogxK

U2 - 10.1016/j.surfcoat.2024.131540

DO - 10.1016/j.surfcoat.2024.131540

M3 - Article

VL - 496.2025

JO - Surface & coatings technology

JF - Surface & coatings technology

SN - 0257-8972

IS - 15 January

M1 - 131540

ER -