The Influence of the Excitation Intensity on the Laser Spectra of acidified Solutions of 4-Methylumbelliferone

Abstract

The influence of the excitation intensity on the laser spectra of solutions of 4-methylumbelliferone in HCl/C₂H₅OH has been investigated. There are three distinct laser emissions at 4100 Å, 4900 Å and 5300 Å, respectively, the third of which only occurs within a HCl-concentration range of 10 -2 m/l < ^cHCl < 2.5 m/l. This emission is quenched if the laser threshold for the emission of the neutral form of 4-methylumbelliferonc at 4100 Å is exceeded.