  A theory of electrical transport through molecular wires is used to estimate
the electronic factor in the intramolecular electron transfer (ET) in
porphyrin-nitrobenzene supermolecules, and to analyze its structure. The chosen
molecules have complex donor and acceptor configurations, and relatively simple
structure of the bridge, which enables us to concentrate our studies on the
donor/acceptor coupling to the bridge. We present analytical and numerical
results concerning the effect of donor/acceptor coupling to the bridge on the
ET process in molecules with complex donor/acceptor subsystems.
  PACS 05.60.Gg, 36.20.-r
