Search

The structural, elastic, magnetic and electronic properties of titanium-based alloys Ti 2 XIn (X = Fe , Co and Ni) are investigated by the first-principles calculations based on density functional theory using the Vienna ab-initio simulation code. The lattice constants of Ti 2 XIn (X = Fe , Co and Ni) alloys are optimized for the two possible structures such as Cu 2 MnAl and Hg 2 CuTi. It is found that at ambient pressure Ti 2 XIn (X = Fe , Co and Ni) alloys are stable in Hg 2 CuTi -type crystal structure. The total magnetic moments (M t ) and the energy gap (E g ) of Ti 2 XIn (X = Fe , Co and Ni) alloys are calculated for various pressures. The total magnetic moments of Ti 2 XIn (X = Fe , Co and Ni) alloys in Hg 2 CuTi structure follow the rule μ t = Z t − 1 8 and agree with the Slater–Pauling (SP) curve quite well. In both structures ( Cu 2 MnAl and Hg 2 CuTi) , the calculated magnetic moment of Ti 2 XIn (X = Fe , Co and Ni) alloys decreases with increase in pressure. Density of states shows the metallic nature of Ti 2 XIn (X = Fe , Co and Ni) alloys in Cu 2 MnAl structure and half-metallic (HM) behavior in Hg 2 CuTi structure, i.e., majority spin channel is strongly metallic and the minority spin maintains the gap at the Fermi level at the equilibrium lattice constant. [ABSTRACT FROM AUTHOR]

The structural, elastic, magnetic and electronic properties of titanium-based alloys TiX2 (X = Cr, Mn) are investigated by the first-principles calculations based on density functional theory using the Vienna ab-initio simulation code. The lattice constants of TiX2 (X = Cr, Mn) alloys are optimized for various possible structures such as hexagonal, tetragonal and orthorhombic. TiX2 (X = Cr, Mn) alloys are highly stable in hexagonal structure with the space group P63/mmc at ambient pressure. A pressure-induced structural phase transition from hexagonal structure to the tetragonal structure is observed in TiCr2 at 443.3 GPa and in TiMn2 hexagonal structure to orthorhombic structure is at 295.05 GPa. The electronic structure shows that TiX2 (X = Cr, Mn) alloys are metallic in nature at all pressures. The magnetic property of nonmagnetic TiX2 (X = Cr, Mn) alloys are analyzed by doping with ferromagnetic materials (Fe, Co and Ni) using the stoichiometries of TiX 2 − z Y z (X = Cr, Mn; Y = Fe, Co and Ni; z = 0.5,1,1.5). It is seen that the magnetic moment is induced by the substitution of ferromagnetic materials with TiX2 alloys. [ABSTRACT FROM AUTHOR]

The structural, elastic, magnetic and electronic properties of titanium-based ferromagnetic (FM) Ti X ( X = Fe, Co, Ni) alloys are investigated by the first principles calculations based on density functional theory using the Vienna ab initio simulation code. At ambient pressure, all the three alloys TiFe, TiCo and TiNi are highly stable in CsCl structure. The calculated lattice parameters and ground state properties are in good agreement with the available theoretical and experimental results. The density of states explains that these alloys possess the metallic nature at normal and high pressures. A pressure-induced structural phase transitions from CsCl to NaCl phase at 46 GPa and NaCl to ZB phase at 49 GPa in TiFe, CsCl to ZB phase in TiCo at 52 GPa, CsCl to hexagonal phase at 22 GPa and hexagonal to ZB phase at 66 GPa in TiNi are observed. The calculated Debye temperatures of Ti X ( X = Fe, Co, Ni) alloys are in good agreement with earlier reports. Binding energy shows that the TiCo is the most stable alloy. The magnetic property of Ti X ( X = Fe, Co, Ni) alloys reveals that TiFe is stable in nonmagnetic phase and the other two alloys, TiCo and TiNi, are stable in FM phase at normal pressure. [ABSTRACT FROM AUTHOR]