Anand, Kanika and Pulikkotil, J. J. and Auluck, S. (2014) Effects of inter-site chemical disorder on the magnetic properties of MnBi. Journal of Magnetism and Magnetic Materials , 363. pp. 18-20. ISSN 0304-8853

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Abstract

Stoichiometric and ordered hexagonal phase of MnBi are difficult to obtain due to the peritectic reaction of the materials constituents. Thus, inter-site mixing of Mn and Bi is expected. Given that the material is a promising rare-earth free permanent magnet, we study the effects of inter-site chemical disorder on its magnetic properties, using ab initio density functional based electronic structure methods. Our calculations, focusing on inter-site substitutional disorder, show that excess of Mn and Bi ions in MnBi have detrimental effects on its magnetic properties. We find that inter-site chemical disorder not only decreases the total magnetization, but also reduces the materials' ferromagnetic transition temperature. The latter is deduced from the calculated magnetic pair-exchange parameters by means of linear response technique. Our calculations suggest that the inter-site disorder of Mn and Bi ions in MnBi must be minimized for its optimum performance in permanent magnet applications. (C) 2014 Elsevier B.V. All rights reserved.

Item Type:	Article
Additional Information:	Copyright for this article belongs to M/S Elsevier.
Subjects:	Materials Science Physics
Divisions:	UNSPECIFIED
Depositing User:	Dr. Rajpal Walke
Date Deposited:	22 Sep 2015 11:08
Last Modified:	22 Sep 2015 11:08
URI:	http://npl.csircentral.net/id/eprint/1256

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