Influence of solvent on spectral and stimulated emission characteristics of iminocoumarin laser dyes

Investigations were made of the spectral, fluorescence, and lasing characteristics of 2-iminocoumarin derivatives. It was established that proton donor solvents have the strongest influence on these characteristics. The structure factor also has a substantial effect. In specific interactions of the molecule the attachment of the diethylamino group in position 7 results in changes in the nonradiative deactivation of its electronic excitation. The characteristics of the solvate effects of iminocoumarins identified can not only increase the spectral tuning range of an active medium utilizing these coumarins, but can also enhance appreciably the efficiency of flashlamp-pumped lasers.