Stilbenes phosphorescence properties

TABLE 15a Phosphorescence Properties of fra/is-Stilbenes in Glassy Media11... 

TABLE 15b Phosphorescence Properties of Substituted fram-Stilbenes"... 

This chapter briefly reviews recent progress in the investigation of fluorescent and phosphorescent properties of stilbenes as well as such phenomena as triplet-triplet and singlet-singlet energy transfer and Raman scattering. The trends in this area include the use of a wide arsenal of stilbenes, employment of elaborated experimental methods such as nano and picosecond time-resolved absorption and fluorescent spectroscopy, and the use of modern theoretical calculations, for example, density function theory. The importance of these research endeavors for further basic and applied applications of stilbenes cannot be overestimated. 

Stilbenes possess a number of photophysical properties, including fluorescence and phosphorescence behavior (Figure 3.1). Because of their high sensitivity, fluorescence and phosphorescence techniques are especially useftd for solving many problems of the structure and dynamics of the chemical, physical, and biological molecular system. 

The absorption and emission spectra and transient triplet-triplet (T-T) absorption spectra of five fluorostilbenes were studied over a wide temperature range, down to 90 K, and compared with stilbene [12]. The phosphorescence spectra of 5,10-dihydro-5,10-dimethylindolo[3,2-b]indole, its 2,7-dicarbethoxy derivatives, and various S and Se analogues of the latter were measured in liquids, glasses, and low-temperature inert gas or N2 matrices [13]. Properties of the triplet state (T-T) absorption spectra (Figure 3.7) and triplet lifetimes of trans-l-(R)-2-(2,4-dinitrophenyl)ethylenes (R 1-naphthyl Ila, 9-anthryl Ilh, styryl lie and 4-(2, 4 -dinitro)- rans-stilbenyl Ild)... 

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