Structure, magnetization, and low-temperature impedance response of polycrystalline InSe intercalated with nickel

A solid-phase mechanochemical technology of production of polycrystalline InSe intercalated with Ni up to 1.25 at. % has been developed. The x-ray and phase analyses of the produced NixInSe samples confirm their homogeneity and demonstrate a nonmonotonic Ni-content dependence of the lattice constant along the axis normal to the layers. Analysis of the low-temperature (77 K) impedance response within the frequency region 10(-3)-10(6) Hz shows a good correlation between the change in interlayer distance and in the band conductivity observed with increasing Ni concentration. However, the Ni concentration dependence of specific magnetization demonstrates an irregular increase at x similar to 1 and does not coincide with the former. Such behavior is explained by the proposed theoretical model, which at the same time unveiled the mechanism behind the increasing contribution of free carrier concentration to conductivity - hybridization of electron orbitals of guest nickel and the lattice layers. (C) 2012 American Institute of Physics. [doi: 10.1063/1.3678440]