Substitution effects on the visible spectra of 1,4-diNHPh-9,10-anthraquinones

With computational chemistry techniques explicitly taking into account electron correlation and solvatation effects, we have investigated the impact of the chemical substitution of 1,4-diNHPh-9,10-anthraquinone on its λmax of absorption in the visible spectra as well as on the corresponding oscillator strength. Although, the impact of chemical substitution on the λmax is less dramatic than for unsubstituted 9,10-anthraquinone, bathochromic (up to +120 nm) and hypsochromic shifts (up to −13 nm) as well as hyper/hypo shifts have been computed. The largest bathoshift has been observed when two (additional) hydrogen bonds are built up between the auxochromic groups and the CO chromophores.