  The close connection of magnetic field structure on the one hand and
observable features of complex ARs with high flare efficiency on the other one
is investigated in frames of so-called dynamic classification of flaring
magnetic configurations (FMC) and the simple topological model of interacting
magnetic complexes (IMC) suggested by Ikhsanov (1982). The primary objective of
the present work is to expose general statements of the specified model and
classification, the secondary one assumes the critical analysis and logical
generalization of several important regularities being frequently observable in
evolution stages of a typical complex AR with powerful flares including proton
ones. Those cases are basically examined where the development of photospheric
situation was marked by the formation of delta-configuration phenomenon
described by Kunzel (1960) as one of the most impressive precursors of high
flare activity. Without trying to use any additional assumptions and
alternative hypotheses, the qualitative analysis of physical reasons and
formative conditions of various delta-configuration classes in solar ARs is
carried out. An attempt to construct the non-contradictory physical
interpretation of morphological, flare-productive and magnetic features of such
configurations is also done. In fact, the authors intend to demonstrate that
the analysis of delta-structure phenomenon from the IMC-based point of view
allows to explain well many early established regularities as kindred phenomena
having the uniform physical reason.
