STUDIES ON THYMINE AND URACIL TRIPLET EXCITED STATE IN ACETONITRILE AND WATER

Abstract

Abstract— Thymine and uracil triplet‐triplet absorption spectra and triplet excited state lifetimes have been observed in acetonitrile and water by nanosecond laser flash spectroscopy. A study of triplet energy transfer from these pyrimidines to retino! has also allowed an estimation of the triplet extinction coefficient ε TT of thymine and uracil. These ε TT were then used to determine the triplet quantum yields Ø T of both pyrimidines in acetonitrile and water.