X-ray Photoemission Spectra and Electronic Structure of Coumarin and its Derivatives.

摘要: The electronic structures of coumarin and three its derivatives (7-amino-4-methylcoumarin, 7-amino-4-(trifluoro)methylcoumarin, 4-hydroxycoumarin) have been studied by theoretical calculations, compared with experimental valence core photoelectron spectra to benchmark the predicted spectra. outer band first compounds showed good agreement calculations for a single isomer, whereas spectrum 4-hydroxycoumarin indicated presence more than one tautomer, consistent published results. Calculations level carbon, nitrogen, oxygen, fluorine are also in satisfactory our measurements. carbon oxygen 1s allow us identify quantify populations principle tautomers present. 4-hydroxy enol form is most stable isomer at 348 K, followed diketo form, 1.3 kJ·mol–1 lower energy.