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Generalized theory of the normal properties of the metal in the case of the electron-phonon (EP) systems with not constant density of electronic states is used to examine the normal state of the SH 3 and SH 2 phase of the hydrogen sulfide at different pressures. The frequency dependence of the real are calculated. The calculations are performed for the stable orthorhombic IM-3M hydrogen sulfide SH 3 structure at three pressures P = 170 GPa, P = 180 GPa, P = 225 GPa and SH 2 structure with the symmetry I4/MMM (D4H-17) for the three values of pressure P = 150 GPa , P = 180 GPa, P = 225 GPa at the temperature of T = 200K.

Éliashberg theory is generalized to the electronphonon (EP) systems with the not constant density of electronic states. The phonon contribution to the anomalous electron Green's function (GF) is considered. The generalized Éliashberg equations with the variable density of electronic states are resolved for the hydrogen sulphide SH 3 phase under pressure. The dependence of both the real and the imaginary part of the order parameter on the frequency in the SH 3 phase is obtained. The Tc = 177 K value in the hydrogen sulfide SH 3 phase at the pressure P = 225 GPa has been defined. The results of the solution of the Eliashberg equations for the Im-3m (170 GPa), Im-3m (200 GPa) and R3m (120 GPa) phases are presented. A peak value Tc = 241 K of the superconducting transition temperature has been predicted. The aim of present work is to derive the generalized Éliashberg equations for the precise Tc calculation in the materials with the strong EP interaction. Such a formalism should allow one a quantitative calculation and prediction of the superconducting properties and Tc in the different phases of the hydrogen sulfide [1, 2], as well as in the high-temperature materials with the EP mechanism of superconductivity, which will be discovered in the near future. We take into account all the features of the frequency behavior of the spectral function of the EP interaction, the behavior of the electronic density of states N 0 (ω) and the specific properties of matter in which the superconducting state is established. The derivation of the Éliashberg equations [13,14] is performed anew on a more rigorous basis, leading to the new terms in the equations for the order parameter. We have taken into account the Coulomb contribution to the order parameter despite the smallness of the Coulomb pseudopotential µ * ≈ 0.1 in the hydrogen sulfide SH 3 phase compared with the significant constant λ ∼ 2.273 of the EP interaction in the sulfide phase. Near Tc the product Reφ (︀ z ′ )︀ Imφ (︀ z ′ )︀ tends to zero for all values of the argument. We obtain omitting the small quantities ImZ (ω), Reχ (ω), Imχ (ω) the following non-linear Unauthenticated Download Date | 5/12/18 10:05 AM Keywords

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