The Electronic and Magnetic Properties of New Full-Heusler Compounds: M2IrSi (M=Ti, Cr and Mn)

Abstract

The half-metallic properties of M2IrSi (M=Ti, Cr and Mn) full-Heusler compounds are studied within the framework of Density Functional Theory (DFT). The ferromagnetic (FM) and non-magnetic (NM) states are compared in Hg2CuTi and Cu2MnAl prototype structures. The FM states in Hg2CuTi structure have been found energetically more stable than NM states for M2IrSi (M=Ti, Cr and Mn) full-Heusler compounds. Due to this stability, all calculations are performed for FM-state. The spin-polarized calculations show that the spin-up electrons of Ti2IrSi compound has metallic nature while spin-down electrons have semiconduction behavior with an energy gap of 0.89 eV. Cr2IrSi compound has metallic properties in both spin-up and spin-down electrons. The spin-up electrons of Mn2IrSi compound has metallic nature while spin-down electrons have semiconduction behavior with an energy gap of 0.41 eV around the Fermi level. Finally, Ti2IrSi compound is a conventional half-metallic ferromagnet and Cr2IrSi compound is metallic ferromagnet within2.73 and 1.0 µB/f.u.magnetic moment, respectively. Mn2IrSi full-Heusler compound is a true half-metallic ferromagnet within 3.0 µB/f.u. magnetic moment.