The effect of temperature on the absorption and fluorescence properties of 1, 4-diphenyl-1, 3-buta-diene (DPB) in poly(vinyl alcohol) film (PVA) was investigated in the range from 293 to 423 K. Upon heating above 353K, the optical density in the long wavelength region (at 339 nm) increases five times only, whereas for l, 6-diphenyl-l, 3, 5-hexatriene (DPH) and l, 8-diphenyl-l, 3, 5, 7-octatetraene (DPO) ten and twenty times, respectively. However, the total quantum yield (ΦF= 0.68) at 293 K is greater than that for the trans-trans form (ΦF= 0.63) and decreases with growing temperature. Both this effect and broadening effect in the fluorescence band at 293 K evidence the existence of two emission centres, i.e. the trans-trans and cistrans conformers.
|Number of pages||7|
|Journal||Zeitschrift fur Naturforschung - Section A Journal of Physical Sciences|
|State||Published - 1 Dec 1992|