science-softCon uv/vis+ spectra data base;		www.uv-spectra.de, (C) science-softCon 2019

Substance: trans-urocanic acid				Other Names: (E)-3-(1H-imidazol-4-yl)prop-2-enoic acid

Formula: C6H6N2O2					CAS-No.: 104-98-3	PubChem: CID 1178

Study: uv absorption spectrum


Authors: K.M. Hanson, B. Li, J.D. Simon

Title: A Spectroscopic Study of the Epidermal Ultraviolet Chromophoretrans-Urocanic Acid

Journal/Source: J. Am. Chem. Soc., 119, 2715-2721, (1997); DOI: 10.1021/ja963440s


Data: diagram, table

Energy/Wavelength range: 230 - 330 nm

Resolution: 

Temperature: 294 - 353 K

Temperature dependence: 

Pressure/Concentration: pH 7.2 buffered, 0.05 mM t-UA

Phase: solution

pH: 7.2


Comments: Excitation of trans-UA at 308 nm (in the tail of the absorption spectrum) does not lead to triplet state formation. Instead, excitation 
at this wavelength leads to isomerization. The quantum yield at this photolysis wavelength is (Phi = 0.49). The absorption maximum is located 
at 277 nm (epsilon = 18800 M-1 cm-1).

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