The Polarized Absorption Spectra of Some β-Substituted Anthraquinones

Abstract

Abstract The polarized absorption spectra of 2-hydroxy-, 2-amino-, and 2,3-diaminoanthraquinones were measured in stretched PVA sheets below 47 kK, and semiempirical ASMO-SCF-CI calculations, including the variable β method, were carried out for these compounds. By a comparison of the observed and the calculated results, the π–π* bands of these compounds were assigned. Each of these compounds has six bands in the observed wave number region, four of which correspond to those of anthraquinone; the other two bands can be assigned to the intramolecular charge-transfer transitions.