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Ni 1 − x TixMnSb polycrystalline alloys in the range 0 ≤ x ≤ 0. 2 0 were synthesized employing the standard solid-phase synthesis method. The crystal, magnetic, as well as electrical properties of the alloys were investigated using neutron powder diffraction and magneto-resistance measurements. The results reveal that the substitution of Ti for Ni within the temperature range of 2.5–300 K does not induce alterations in the crystal and magnetic structures of NiMnSb. The ordered Ni magnetic moment approaches zero. The study of the electrical transport properties of the Ni 1 − x TixMnSb alloys, where 0 ≤ x ≤ 0. 2 0 , has demonstrated a half-metallic state at low temperatures and metallic conductivity for temperatures exceeding 160 K. A semiconductor state manifests at titanium concentrations of x = 0.2 and was observed at temperatures below 21 K. The obtained experimental results are elucidated through first-principles theoretical calculations. [ABSTRACT FROM AUTHOR]

The structural and magnetic properties of Bi0.5La0.5Fe1−xCrxO3−δ (x = 0, 0.05, 0.10, 0.20, and 0.40) compounds synthesized by a solid-state reaction method have been investigated. Rietveld refinement of x-ray and neutron powder diffraction data revealed a nonpolar orthorhombically distorted perovskite Pnma structure with long-range G-type antiferromagnetic (AFM) order in the studied samples. It was observed that substitution by Cr strongly influenced the morphology, crystalline, and magnetic properties of the samples. Interestingly, Cr doping led to an abrupt increase in the crystallite size from 31 nm for x = 0 to 740 nm for x = 0.40. This size change was accompanied by a decrease of microstrain by about twofold and a sudden change of the structural parameters. Magnetization measurements indicated the coexistence of ferromagnetic (FM) clusters with long-range AFM order. It was established that Cr doping leads to a suppression of the magnetic states. More interestingly, all of the samples demonstrated a spontaneous large exchange bias (EB) effect at room temperature, which is of great interest from the viewpoint of practical applications. The EB effect originates from pinning of uncompensated spins at the interfaces between FM clusters and the AFM matrix. [ABSTRACT FROM AUTHOR]