Fluorescence spectrum, anthracene phenanthrene

Chandross, Longworth, and Visco126 have reported the observation of long-wave structureless emission bands in the vicinity of the electrodes during the ac electrolysis of anthracene, phenanthrene, perylene, and 3,4-benzpyrene in polar solvents such as acetonitrile and dimethylformamide the similarity between the perylene band and the crystal fluorescence spectrum prompted the assignment of these bands to excimer fluorescence originating in the process... 

Figure 6. (a) Fluorescence spectrum of a mixture of naphthalene, phenanthrene, anthracene, perylene, ana tetracene (Xga. = 258 nm). (b) Synchronous signal (AX = 3 nm) of the same mixture. 

Figure 2.19. Left molecular spectra of phenanthrene. Right fluorescence spectrum 1 ppm anthracene in ethanol. Right, top excitation spectrum right, bottom emission spectrum...

Monoclinic plates from ale. Sublimes. When pure, colorless with violet fluoresence when impure (due to tetracene, naphthacene), yellow with green fluorescence. Strongly triboluminescent and triboelectric. dj 1.25. mp 218. bp,M 342. Absorption spectrum Clar, Ber. 65, 506(1932). Less soluble than the isomeric phenanthrene. Insol in water one gram dissolves in 67 ml abs alcohol, 70 ml methanol, 62 ml benzene, 85 ml chloroform, 200 ml ether, 31 ml carbon disulfide, 86 ml carbon tetrachloride, 125 ml toluene. Anthracene darkens in sunlight. According to Downs, U.S. pat. 1,303.639 (1919), when solns of crude anthracene in coal tar naphtha are exposed to ultraviolet irradiation, the anthracene is precipitated as dianthracene (para-anthracene) which is reconverted to anthracene by sublimation. 

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