First-principles study of half-metallic properties of the Heusler alloy Ti2CoGe

• Published in: Journal of magnetism and magnetic materials 2012-08, Vol.324 (16), p.2560-2564
• Main Authors: Huang, H.M., Luo, S.J., Yao, K.L.
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electron density of states and band structure of crystalline solids; Electron states; Energy gap; Exact sciences and technology; Fermi surfaces; Ferromagnetism; First-principles; Half-metallicity; Heusler alloy; Heusler alloys; Lattice parameters; Magnetic properties; Magnetic properties and materials; Magnetism; Mathematical analysis; Other ferromagnetic metals and alloys; Other inorganic compounds; Physics; Studies of specific magnetic materials
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2012.03.047

First-principles calculations have been performed on the electronic structures and magnetic properties of a new Ti2Co-based full-Heusler alloy Ti2CoGe. The calculations predict the Ti2CoGe is a half-metallic ferromagnet at the equilibrium lattice constant with the minority-spin energy gap of 0.60eV. It is found that the total magnetic moment (Mt) and the number of valence electrons (Zt) in Ti2CoGe obey a new Slater–Pauling (SP) rule of Mt=Zt−18 and the rule also can be applied to other Ti2Co-based half-metallic full-Heusler alloys. The Ti2CoGe alloy keeps a 100% polarization at Fermi level and maintains the half-metallic character for lattice constants ranging between 6.05 and 6.67Å. ► The Ti2CoGe alloy in CuHg2Ti-type structure is predicted to being half-metallic ferromagnetic nature. ► A new Slater–Pauling rule of Mt=Zt−18 in normal Ti2Co-based half-metallic full-Heusler alloys has been proposed. ► The half-metallic character of Ti2CoGe can be maintained for the range between 6.05 and 6.67Å.