PHYSICAL PROPERTIES AND CHEMICAL REACTIVITY OF ALTERNANT HYDROCARBONS AND RELATED COMPOUNDS .17. ELECTRONIC SPECTRA OF AMINO AND HYDROXY DERIVATIVES OF BENZENOID HYDROCARBONS

The electronic absorption spectra of the monoamino and monohydroxy derivatives of benzene, naphthalene, and of derivatives of phenanthrene, pyrene, and benzo[c]phenanthrene were recorded in 50% aqueous methanol and in alkaline (0.2 M NaOH) 50% aqueous methanol. For 11 representatives, the position of the first S→T1 transitions were estimated from phosphorescence spectra. It was found that several first bands of the absorption curves (S0→Sx transitions) can be reasonably interpreted by means of the unmodified method of Pariser, Parr, and Pople, using the Mataga-Nishimoto approximation for the electron repulsion integrals.