LOW TEMPERATURE PECULIARITIES OF NONRADIATIVE MIGRATION OF THE ELECTRONIC EXITATION ENERGY IN THE INHOMOGENEOUS ENSEMBLE OF DIE MOLECULES ADSORBED IN POROUS GLASS
Creators:Beger, V. N.
MetadataShow full item record
Publisher:Ohio State University
It has been discovered that in the case of low temperatures (about 77K) and of laser exitation the increasing of concentration of dye molecules in porous glass causes both the removal of fluorescence spectra of the adsorbates towards the side of long waves (that also takes place in the case of room temperature) and significant modification of the shape of these spectra. In the case of high concentration of adsorbed molecules and of low enough temperature the fluorescence spectra of some adsorbed dyes turn into the superposition of a few bands. The first band coincides with the fluorescence spectrum of the same adsorbate of low concentration and each of the next bands has the same shape and width as previous band, but each of them is shifted relatively previous band towards the side of long waves. The value of this shift is approximately equal to the Stokes shift between maximun of the absorption spectrum and maximum of the fluorescence spectrue of the adsorbate of low concentration. Discovered phenomenon is caused by the specific character of nonradiative nigration of electronic exitation energy under conditions of nonunifore broadening of anergetic levels of adsorbed molecules. The revealed temperature peculiarities of the energy migration may be explained by the increasing of the selectivity of the migration under low temperature conditions.
Author Institution: Saint-Petersburg, Russia. 197101.
Items in Knowledge Bank are protected by copyright, with all rights reserved, unless otherwise indicated.