In situ synthesis, photometric and spectroscopic studies of chelating system during the 1,4,7,10,13,16-hexaoxacyclooctadecane charge transfer reaction with different acceptors

► Donor-acceptor complexes of 18-crown-6 as a rich donor were discussed in solution and solid form. ► Spectroscopic data such as KCT, ɛCT, ΔG°, f, μ, RN and Ip were estimated. ► The charge-transfer interactions formed dative ion pairs [18C6+, A-], where A is acceptor.