Ultraviolet resonance Raman spectroscopy of 4-aminopyridine adsorbed on zeolite Y

Fourier Transform Raman Spectroscopy of Sorbed HDTMA and the Mechanism of Chromate Sorption to Surfactant-Modified Clinoptilolite

“…The corresponding peak in the 160% level is broad, so this relative shift is indistinct but may indicate more water available to the headgroups as monolayer density is decreased. Nitrogen bands in pyridine−water mixtures also shift to higher frequencies upon hydration ( , ). Water has been noted to exist between head groups and silver island surfaces in previous studies of sorbed HDTMA monolayers ().…”

“…These sites on adsorbates are known to affect the polarizability and dipole moment of the conjugate acid or base and, thus, the Raman and IR band frequencies ( 10, 16, 18 and others cited therein). Lewis acid sites occur when the zeolites have been completely alkali-exchanged and dried under vacuum ( , ). The presence of the surfactant may substantially reduce the amount of near-surface water in aqueous systems, enhancing the relative acidity of such sites and subsequently promoting chromate sorption.…”

Crystal Structure and Band Gap Engineering in Polyoxometalate-Based Inorganic–Organic Hybrids

“…The spectra have contributions from the inorganic (POM) and organic moiety (Cu–bpy for the compounds 1a , 1b , and 3 , see Figure S7, bpy for the compounds 2 and 4 ). The POM peaks were assigned (Supporting Information Tables S2–S4) using the previous reports − on the Keggin structure. , The POM peaks are present mostly below 1000 cm –1 , and the peaks above 1000 cm –1 are found to be predominantly due to Cu–bpy/bpy vibrations. , The major peaks of POM were found to be similar in all of the compounds, though POM vibrations in the Raman spectra of compounds 1b and 3 were very weak. Raman and IR band assignment for modes of all compounds are listed in Tables S2 and S3, respectively.…”

“…56,57 The POM peaks are present mostly below 1000 cm −1 , and the peaks above 1000 cm −1 are found to be predominantly due to Cu− bpy/bpy vibrations. 58,59 The major peaks of POM were found to be similar in all of the compounds, though POM vibrations in the Raman spectra of compounds 1b and 3 were very weak. Raman and IR band assignment for modes of all compounds are listed in Tables S2 and S3, respectively.…”

The First Raman Spectrum of an Organic Monolayer on a High-Temperature Superconductor: Direct Spectroscopic Evidence for a Chemical Interaction between an Amine and YBa2Cu3O7-δ

“…Three strong bands were observed in the 1100−750 cm -1 region of the SERS spectrum of the 4-aminopyridine monolayer (Figure B). On the basis of the band assignments made by Spinner for solid 4-aminopyridine, we assign the two monolayer bands centered at 1006 and 1052 cm -1 to the ring-breathing and deformation modes of the pyridinal ring, respectively. The out-of-plane C−H bending vibration mode also is observed at 853 cm -1 12a…”