Persistent hole burning of 1,4-disubstituted anthraquinone molecules

1,4-disubstituted anthraquinones with two electron-donating groups, such as hydroxy, amino and stearylamino groups, are investigated on hole burning and its efficiency in polar low-temperature matrices (4.7 K). The efficiency decreased significantly when the two hydroxy groups of quinizarin were substituted by amino or stearylamino group(s). The efficiency of those molecules in which only one hydroxy group was substituted was about two orders of magnitude smaller than that ofquinizarin. These results suggest that the photoproduct of quinizarin is related to light-induced changes in both functional groups which are stabilized through intermolecular hydrogen bonds with the matrix.