General theory of Weller Scheme I of exciplex formation

►The Weller Scheme I of exciplex formation is considered within the Integral Encounter Theory accounting for the reaction reversibility and continuation. ► The spin-conversion in radical ion pair arising from the exciplex dissociation is accounted for allowing the ions recombination to triplet excitations. ► The natural decay of triplets is taken into account as well as their impurity quenching in the bulk encounters. ► The Stern-Volmer constant of stationary fluorescence is specified at different free energies of exciplex ionization and spin-conversion rates.