The effect of temperature on the fluorescence properties of 1,8-diphenyl-1,3,5,7-octatetraene (DPO) in poly(vinyl alcohol) film (PVA) was investigated in the range from 295 to 428 K. Upon heating above 353 K, the quantum yield of DPO increases rapidly. This effect is irreversible, similarly as the optical density in the long wavelength absorption band (320–440 nm). It has its origin in the cis-trans conversion of DPO molecules in PVA film at high temperatures. The behaviour of the fluorescence anisotropy in the same temperature range was also investigated. The emission anisotropy was found to be a viscosity indicator in the microenvironment of the DPO molecules in PVA film.
|Number of pages||6|
|Journal||Zeitschrift fur Naturforschung - Section A Journal of Physical Sciences|
|State||Published - 1 Oct 1992|