作者: Julius C. Fister , Joel M. Harris
DOI: 10.1021/AC950738C
关键词: Singlet fission 、 Acridine yellow 、 Chemistry 、 Excited state 、 Singlet state 、 Intersystem crossing 、 Phosphorescence 、 Population 、 Triplet state 、 Photochemistry
摘要: Multiwavelength time-resolved spectroscopy is employed to study the triplet-state photophysics of acridine yellow dissolved in a rigid saccharide glass. Activated reverse intersystem crossing from photoexcited triplet states fluorescent singlet state provides temperature-dependent decay pathway population. While unimolecular relaxation homogeneous excited population would result single-exponential delayed-fluorescence intensity, nonexponential was observed at all temperatures. Multidimensional regression analysis time- and wavelength-resolved fluorescence phosphorescence emission found be powerful method investigate an inhomogeneous matrix, where two discrete populations are found. From temperature dependence their rates, energy barriers activated determined compared triplet−singlet gaps determine...