Raman and surface-enhanced Raman spectra of chrysin, apigenin and luteolin

Phenolic compound explorer: A mid-infrared spectroscopy database

“…, which could be helpful in discriminating the different structures of flavones [44]. In the present study, flavonols, flavones and isoflavones showed several bands in the ranges described )).…”

A conformational study of hydroxyflavones by vibrational spectroscopy coupled to DFT calculations

“…Despite the considerable amount of work reported for these systems both by Raman and SERS techniques [51][52][53][54], a complete and accurate assignment has not yet been achieved. Furthermore, FTIR has a huge potential for the study of this kind of polyhydroxylated compounds [47,[55][56][57].…”

Surface‐enhanced Raman spectroscopy of indanthrone and flavanthrone

“…This scaling is commonly needed in DFT calculations of Raman spectra in order to correct for correlation effects incompletely accounted for in DFT. We have found the piecewise scaling to be quite valuable in fitting spectra of related compounds, [12,13] since the correction has a slightly different effect on different bonds, and this is reflected in different regions of the spectrum. In instances where there was spectral congestion, such as in the carbonyl stretch region (near 1600 cm −1 ), the relative intensities of the calculated spectra were matched to those of the observed spectra, so that the most intense calculated lines were assigned to the most intense observed lines.…”

“…This same behavior has also been observed in the spectra of several flavones. [12,13] The absence of this band in the DFT calculation can be ascribed to the fact that the DFT calculation is carried out considering the molecule in the vacuum, whereas the FT Raman spectrum is of a crystalline sample. The 1662 cm −1 band is most likely due to interactions of the carbonyl stretching modes of adjacent molecules in the crystalline structure, which would be absent in the solution or gas phase spectra.…”

“…[6,7] Recently, SERS has demonstrated its potential in the analysis of organic natural dyes, mostly anthraquinones [8 -11] and flavonoids. [12,13] Few Raman spectra of indanthrone can be found in the literature. For example, the normal Raman spectrum of the pigment at 785 nm was used to identify the colorant in a cross section of a green automotive paint.…”