Spin-Fluctuation Mechanism of Superconductivity of Strongly Correlated Transition Metal Compounds with pd-Hybridization

The electronic spectrum and the spin-fluctuation mechanism of superconductivity for strongly correlated transition metal compounds with strong pd-hybridization are investigated. It was found that hybridization of strongly correlated electrons and with nearly free electrons leads to a picture of p- and d-like zones separated by the Hubbard gap. Instability of system of electrons to magnetism and to d-symmetric superconductivity for considered quasi-planar crystals is discussed within the framework of the spin-fluctuation theory. Comparison of the results of calculations of the electronic spectra of lanthanum cuprates compounds with earlier calculations for isostructural manganites of lanthanum has been carried out. It is important to say that the decrease of the parameter of the Hubbard interaction and the Fermi level position (at a constant hybridization potential) leads to the replacement of magnetic solutions on solutions describing instability to emergence of superconductivity. Analysis of the magnetic properties has been made on example of La2−xSrxCuO4.