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

Jakupca, Michael R.; Dutta, Prabir K.

doi:10.1021/ac00032a021

Cited by 16 publications

(9 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…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 ().…”

Section: Resultsmentioning

confidence: 99%

“…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.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

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

Sullivan

Hunter

Bowman

1998

Environ. Sci. Technol.

View full text Add to dashboard Cite

We examined sorption of the cationic surfactant hexadecyltrimethylammonium bromide (HDTMA) to clinoptilolite zeolite and the subsequent sorption of the chromate anion to surfactant-modified zeolite (SMZ). We used Fourier transform (FT) Raman spectroscopy and batch sorption methods to elucidate the structure of sorbed HDTMA and to determine the mechanisms of chromate sorption. At high HDTMA loading levels (above the zeolite's external cation exchange capacity, ECEC), the Raman spectra indicated that sorbed HDTMA was similar in conformation to solution micelles and, thus, may contain anion exchange sites. Sorbed HDTMA showed less structuring of tail groups and a decrease in head group hydration. At lower loadings, the sorbed HDTMA tail groups tended to have more disorder, similar to solution monomers. When HDTMA loading rates were greater than 100% of the ECEC, chromate sorbed onto SMZ with near-equivalent Br- counterion exchange. A peak in the Raman spectrum at 902 cm-1 indicated the presence of sorbed Cr2O7 2-, although no bulk solution oligomerized chromate species should have been present at a solution pH of 7. A 30 cm-1 shift in the ν1 peak for sorbed versus solution chromate may indicate that surface-enhanced Lewis acid−base interactions were responsible for some chromate sorption in addition to the predominant anion-exchange mechanism.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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

Sullivan

Hunter

Bowman

1998

Environ. Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…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.…”

Section: Resultsmentioning

confidence: 98%

“…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.…”

Section: Methodsmentioning

confidence: 95%

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

et al. 2016

View full text Add to dashboard Cite

We have demonstrated engineering of the electronic band gap of the hybrid materials based on POMs (polyoxometalates), by controlling its structural complexity through variation in the conditions of synthesis. The pH- and temperature-dependent studies give a clear insight into how these experimental factors affect the overall hybrid structure and its properties. Our structural manipulations have been successful in effectively tuning the optical band gap and electronic band structure of this kind of hybrids, which can find many applications in the field of photovoltaic and semiconducting devices. We have also addressed a common crystallographic disorder observed in Keggin-ion (one type of heteropolyoxometalate [POMs])-based hybrid materials. Through a combination of crystallographic, spectroscopic, and theoretical analysis of four new POM-based hybrids synthesized with tactically varied reaction conditions, we trace the origin and nature of the disorder associated with it and the subtle local structural coordination involved in its core picture. While the crystallography yields a centrosymmetric structure with planar coordination of Si, our analysis with XPS, IR, and Raman spectroscopy reveals a tetrahedral coordination with broken inversion symmetry, corroborated by first-principles calculations.

show abstract

“…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…”

mentioning

confidence: 99%

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

Zhu

Schofer

et al. 1997

J. Am. Chem. Soc.

View full text Add to dashboard Cite

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

Cited by 16 publications

References 27 publications

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

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

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

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

Contact Info

Product

Resources

About

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

Cited by 16 publications

References 27 publications

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

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

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

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

Contact Info

Product

Resources

About

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