The molecular ditance dependence of the fluorescence depolarization caused by enerugy transfer in 5CB between dichroic dyes

Abstract

Fluorescence depolarization of energy acceptors caused by nenergy transfer between dichroic dyes in 5CB has been investigated using UV absorbing energy donors(BBOT, D-POPOP) and energy accepters(Coumarin521,540). A parameter H, which indicates the degree of depolarization of the fluoresence, has been introduced taking account of the anisotropy of the liquid crystal cells. The relation between the intermolecular distance R and the values of H is discussed when the dye concentrations are changed.