Premium
LOCAL ELECTRIC FIELD EFFECT ON THE CHLOROPHYLL FLUORESCENCE
Author(s) -
Frackowiak D.
Publication year - 1978
Publication title -
photochemistry and photobiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.818
H-Index - 131
eISSN - 1751-1097
pISSN - 0031-8655
DOI - 10.1111/j.1751-1097.1978.tb07721.x
Subject(s) - electric field , absorption (acoustics) , fluorescence , chemistry , liquid crystal , chemical physics , materials science , photochemistry , analytical chemistry (journal) , local field , chlorophyll fluorescence , molecular physics , optics , optoelectronics , physics , organic chemistry , condensed matter physics , quantum mechanics , composite material
. Polarized absorption and fluorescence of chlorophyll a and bacteriochlorophyll solutions in nematic liquid crystal mixtures have been studied in the presence of an external electric field. The electric field caused a reorientation of the pigment molecules as concluded from changes in the polarized absorption. However, no correlation was found between the change in the polarized absorption and the change in the polarized fluorescence as a function of the field strength. The field influence was much stronger than expected only from the molecular orientation. The fluorescence polarized parallel to the direction of the liquid crystal was found to increase, whereas the similarly polarized absorption decreases. As a whole, the fluorescence yield significantly increased. It is suggested that the additional electric field is reinforced by a local field, most probably due to a protonation of the liquid crystal molecules. Charged solvent molecules are reoriented in an external electric field which changes the local electric field acting on chlorophylls. Similar changes in CHI fluorescence yield due to local electric field can be created in vivo by the shift of charged molecules present in surrounding pigments. Such effects can be at least partially responsible for slow induction of fluorescence phenomena.