Ni excess and electronic structures of multi-functional Ni_{2.17}Mn_{0.83}Ga

Article type: Research Article

Authors: Ishida, Shoji^a | Furugen, Munemasa^a | Asano, Setsuro^b

Affiliations: [a] Department of Physics, Faculty of Science, Kagoshima University Korimoto1-21-35, Kagoshima 890-0065, Japan. Tel./Fax: +81 285 8070; E-mail: ishida@sci.kagoshima-u.ac.jp | [b] Institute of Physics, College of Arts and Sciences, University of Tokyo Komaba 3-8-1, Meguro-ku, Tokyo 153-0041, Japan. Tel: +81 3 5454 6513; Fax: +81 3485 2904; E-mail: asano@atom.c.u-tokyo.ac.jp

Abstract: The electronic structures of Ni_{2.17}Mn_{0.83}Ga predict that the tetragonal, the orthorhombic and the monoclinic structure can be a martensitic phase and the monoclinic structure is the most stable. The stabilization of the monoclinic structure mainly comes from the difference of the kinetic energy. Then, the Ni excess plays an important role in the stabilization of the crystal structure. The Ni excess atoms make the tetragonal and orthorhombic structures unstable and the monoclinic structure stable. It is also found that the Ni excess atoms prefer the Mn sites and the magnetic moments in the monoclinic structure are smaller than those in the other structures.

DOI: 10.3233/JAE-2000-190

Journal: International Journal of Applied Electromagnetics and Mechanics, vol. 12, no. 1-2, pp. 41-48, 2000