  Earlier we have proposed a new approach to the analysis of superconducting
phase diagrams for cuprates and pnictides and have shown that the positions of
superconducting domes on the diagrams can be predicted with high accuracy
proceeding from only the crystal structure of a particular compound. The
proposed approach uses the concept of the self-localization of doped carriers
due to their formation of trion complexes that represent a bound state of the
doped carrier and charge transfer excitons emerging under its influence. Here,
as exemplified by cuprates, we show that the use of the proposed approach to
the analysis of the transformation of an electronic structure with doping
enables an explanation to a range of their anomalies: Fermi arcs, large and
small pseudogaps etc. The basic conclusion is that the role of the Fermi
surface in cuprates is played by an isoenergetic contour that emerges at the
sectioning of the surface of a band dispersion by a dispersionless "biexciton"
pair level. This level additionally plays the role of an acceptor to lead to
the emergence of hole carriers on the isoenergetic contour and to a jump of the
chemical potential. Based on the conducted consideration, we propose a possible
mechanism of superconducting pairing genetically inherent in such a system.
