As of 1 April 2026, the PSJD database will become an archive and will no longer accept new data. Current publications from Polish scientific journals are available through the Library of Science: https://bibliotekanauki.pl
Analytical expressions of profiles of absorption and instantaneous fluorescence spectra of dye molecules in polar solvents are given. It is shown what parameters can be gained from electronic spectra of dye solutions. The new procedure of interpretation of transient fluorescence spectra is demonstrated in the case of the spectra of nile blue in alcohol.