A SPECTROPHOTOMETRIC STUDY OF CHARGE-TRANSFER COMPLEXES OF 1,4-DIMETHOXYNAPHTHALENE AND 1,8-DIMETHOXYNAPHTHALENE

1,4- and 1,8-dimethoxynapthalene (DMN) have been synthesized, their ch arge transfer complexes (CTCs) with organic accepters such as 2,3-dicy ano-5,6-dichlorobenzoquinone (DDQ), 7,7,8,8-tetracyanoquinodimethane ( TCNQ), bromanil (BRL) and picric acid (PIG) have been studied at vario us temperatures in CH2Cl2. The data are discussed in terms of equilibr ium constant (K-4), thermodynamic reaction quantities (Delta H degrees Delta S degrees and Delta G degrees) and transition energies of the c omplexes. The stability of these complexes depends on the electron aff inities of the accepters in addition to the geometrical structure of t he donors, where the ionization potential of the donor show a small ne gligible effect. The best values of K-4 and molar absorption coefficie nts epsilon 4 of all systems were obtained through an iterative proced ure employing a computer program by using linear regression fit.