Initial hydrogen-bonding dynamics of photoexcited coumarin in solution with femtosecond stimulated Raman spectroscopy

2016 ◽  
Vol 4 (14) ◽  
pp. 2954-2963 ◽  
Author(s):  
Fangyuan Han ◽  
Weimin Liu ◽  
Liangdong Zhu ◽  
Yanli Wang ◽  
Chong Fang
Keyword(s):  
Hydrogen Bond ◽  
Raman Spectroscopy ◽  
Hydrogen Bonding ◽  
Bond Breaking ◽  
Coumarin 102 ◽  
Hydrogen Bonding Dynamics ◽  
Dye Molecule ◽  
Stimulated Raman

The ultrafast hydrogen bond breaking and reformation dynamics at the carbonyl site of a coumarin 102 dye molecule in ethanol is captured by femtosecond stimulated Raman spectroscopy (FSRS) on the femtosecond and picosecond timescales.

The effects of selected gases upon ethanol: hydrogen bond breaking by O2 and N2

1985 ◽  
Vol 63 (7) ◽  
pp. 1864-1869
Author(s):  
T. L. Mathers ◽  
G. Schoeffler ◽  
S. P. McGlynn
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Aromatic Hydrocarbons ◽  
Bonding Process ◽  
Bond Breaking ◽  
Temperature Dependency ◽  
Normal Hydrogen ◽  
Luminescence Characteristics

The temperature dependency of the phosphorescence properties of aromatic hydrocarbons in alcoholic glasses exhibits a number of phenomena that have not been described previously. Chief among these are the effects of added gases (O2, N2, C2H6, Ar), some of which produce major changes in the luminescence characteristics. These are discussed, and rationalized in terms of a model which presumes that O2 and N2 can disrupt the normal hydrogen bonding process between alcohol molecules.

Anesthesia and hydrogen bonding. A semi-quantitative infrared study at room temperature

1978 ◽  
Vol 56 (12) ◽  
pp. 1681-1686 ◽  
Author(s):  
Ginette Trudeau ◽  
K. C. Cole ◽  
Rachel Massuda ◽  
C. Sandorfy
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Hydrogen Bonds ◽  
Room Temperature ◽  
Quantitative Relationship ◽  
Bond Breaking ◽  
Infrared Study ◽  
Text Types ◽  
Theories Of Anesthesia ◽  
Anesthetic Potency

It has been shown previously that certain anesthetics hinder the formation of hydrogen bonds of the [Formula: see text] types. An attempt bas now been made to correlate this hydrogen bond 'breaking' property with anesthetic potency. As a measure of the former, relative intensifies of infrared bands related to 'free' and hydrogen bonded species were used. The band which was chosen for this purpose is the OH or NH stretching + in-plane bending combination band. This made it possible to carry out the measurements at room temperature. A semi-quantitative relationship has been found. Its significance for the theories of anesthesia is discussed.

scholarly journals Infrared and Raman Spectroscopy of Ammoniovoltaite, (NH4)2Fe2+5Fe3+3Al(SO4)12(H2O)18

Minerals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 781
Author(s):  
Anastasia V. Sergeeva ◽  
Elena S. Zhitova ◽  
Anton A. Nuzhdaev ◽  
Andrey A. Zolotarev ◽  
Vladimir N. Bocharov ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Raman Spectroscopy ◽  
Hydrogen Bonding ◽  
Raman Spectrum ◽  
Local Symmetry ◽  
Geothermal Field ◽  
Infrared And Raman Spectra ◽  
Infrared And Raman Spectroscopy ◽  
Related Compounds

Ammoniovoltaite, (NH4)2Fe2+5Fe3+3Al(SO4)12(H2O)18, is a complex hydrated sulphate of the voltaite group that has been recently discovered on the surface of the Severo-Kambalny geothermal field (Kamchatka, Russia). Vibrational spectroscopy has been applied for characterization of the mineral. Both infrared and Raman spectra of ammoniovoltaite are characterized by an abundance of bands, which corresponds to the diversity of structural fragments and variations of their local symmetry. The infrared spectrum of ammoniovoltaite is similar to that of other voltaite-related compounds. The specific feature related to the dominance of the NH4 group is its ν4 mode observed at 1432 cm−1 with a shoulder at 1510 cm−1 appearing due to NH4 disorder. The Raman spectrum of ammoniovoltaite is basically different from that of voltaite by the appearance of an intensive band centered at 3194 cm−1 and attributed to the ν3 mode of NH4. The latter can serve as a distinctive feature of ammonium in voltaite-group minerals in resemblance to recently reported results for another NH4-mineral—tschermigite, where ν3 of NH4 occurs at 3163 cm−1. The values calculated from wavenumbers of infrared bands at 3585 cm−1, 3467 cm−1 and 3400 cm−1 for hydrogen bond distances: d(O···H) and d(O···O) correspond to bonding involving H1 and H2 atoms of Fe2+X6 (X = O, OH) octahedra. The infrared bands observed at 3242 cm−1 and 2483 cm−1 are due to stronger hydrogen bonding, that may refer to non-localized H atoms of Al(H2O)6 or NH4.

scholarly journals Crystal structure of a 2:1 piroxicam–gentisic acid co-crystal featuring neutral and zwitterionic piroxicam molecules

2016 ◽  
Vol 72 (12) ◽  
pp. 1714-1717
Author(s):  
Elizabeth M. Horstman ◽  
Jeffery A. Bertke ◽  
Toby J. Woods ◽  
Paul J. A. Kenis
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Raman Spectroscopy ◽  
Hydrogen Bonding ◽  
The Other ◽  
Acid Molecule ◽  
Dihydroxybenzoic Acid ◽  
Neutral Form ◽  
Gentisic Acid ◽  
Whole Molecule Disorder

A new 2:1 co-crystal of piroxicam and gentisic acid [systematic name: 4-hydroxy-1,1-dioxo-N-(pyridin-2-yl)-2H-1λ6,2-benzothiazine-3-carboxamide–2-(4-oxido-1,1-dioxo-2H-1λ6,2-benzothiazine-3-amido)pyridin-1-ium–2,5-dihydroxybenzoic acid, 2C15H13N3O4S·C7H6O4] has been synthesized using a microfluidic platform and initially identified using Raman spectroscopy. In the co-crystal, one piroxicam molecule is in its neutral form and an intramolecular O—H...O hydrogen bond is observed. The other piroxicam molecule is zwitterionic (proton transfer from the OH group to the pyridine N atom) and two intramolecular N—H...O hydrogen bonds occur. The gentisic acid molecule shows whole-molecule disorder over two sets of sites in a 0.809 (2):0.191 (2) ratio. In the crystal, extensive hydrogen bonding between the components forms layers propagating in theabplane.

scholarly journals Raman Spectroscopy for the Competition of Hydrogen Bonds in Ternary (H2O–THF–DMSO) Aqueous Solutions

Molecules ◽  
2019 ◽  
Vol 24 (20) ◽  
pp. 3666
Author(s):  
Liu ◽  
Zhang ◽  
Huang ◽  
Wu ◽  
Ouyang
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Bond ◽  
Raman Spectroscopy ◽  
Hydrogen Bonding ◽  
Hydrogen Bonds ◽  
Aqueous Solutions ◽  
Dimethyl Sulfoxide ◽  
Water Molecules ◽  
Bonding Theory ◽  
Hydrogen Bonded

The effects of hydrogen bonds on the molecular structure of water-tetrahydrofuran (H2O–THF), water-dimethyl sulfoxide (H2O–DMSO), and water-tetrahydrofuran-dimethyl sulfoxide (H2O–THF–DMSO) in binary aqueous solutions and ternary aqueous solutions were studied using Raman spectroscopy. The results indicate that in the binary aqueous solution, the addition of THF and DMSO will generate hydrogen bonds with water molecules, resulting in changes in the peak positions of S=O bonds and C–O bonds. Compared with the binary aqueous solutions, the hydrogen bonds between DMSO and THF, and the hydrogen bonds between DMSO and H2O in the ternary aqueous solutions are competitive, and the hydrogen bond competition is susceptible to water content. In addition, the formation of hydrogen bonds will destroy the fully hydrogen-bonded water and make it change to the partially hydrogen-bonded water. By fitting the spectra into the three Gaussian components assigned to water molecules with different hydrogen bonding (HB) environments, these spectral features are interpreted by a mechanism that H2O in different solution systems has equal types of water molecules with similar HB degrees-fully hydrogen-bonded H2O (FHW) and partially hydrogen-bonded H2O (PHW). The ratio of the intensity transition from FHW to PHW is determined based on Gaussian fitting. Therefore, the variation of hydrogen bond competition can be supplemented by the intensity ratio of PHW/FHW ((IC2 + IC3)/IC1). This study provides an experimental basis for enriching the hydrogen bonding theory of multivariate aqueous solution systems.

Investigation of the Origin of Voltage Generation in Potentized Homeopathic Medicine through Raman Spectroscopy

Homeopathy ◽  
2019 ◽  
Vol 108 (02) ◽  
pp. 121-127 ◽  
Author(s):  
Tara Bhattacharya ◽  
Payaswini Maitra ◽  
Debbethi Bera ◽  
Kaushik Das ◽  
Poonam Bandyopadhyay ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Raman Spectroscopy ◽  
Hydrogen Bonding ◽  
Electrical Properties ◽  
Hydrogen Bonds ◽  
Vibrational Spectra ◽  
Strong Hydrogen Bond ◽  
Oh Groups ◽  
Homeopathic Medicine ◽  
Presence And Absence

Background For the study of homeopathic medicines in proper perspective, emerging techniques in material science are being used. Vibrational spectroscopy is one such tool for providing information on different states of hydrogen bonding as an effect of potentization. The associated change in electrical properties is also correlated with this effect. Objective From the vibrational spectra, the changes in hydrogen bonding due to dilution followed by unidirectional vigorous shaking (together termed potentization) of 91% ethanol and two homeopathic medicines Chininum purum and Acidum benzoicum have been studied. The aim was to correlate the result with the change in the electrical properties of the system. Methods Raman spectroscopy was used to study the vibrational spectra. A U-shaped glass tube (electrochemical cell), where one arm contained bi-distilled water and the other arm alcohol/homeopathic medicine (the arms being separated by a platinum foil), was used to measure the voltage generated across two symmetrically placed platinum electrodes. Results For all samples, it was observed that potentization affected the intensity of OH stretching bands at the frequencies 3240 cm−1, 3420 cm−1 and 3620 cm−1, corresponding to strong hydrogen bond, weak hydrogen bond and broken hydrogen bond, respectively. With the increase in potency, in the presence and absence of the two medicines in ethanol, the number of OH groups linked by strong hydrogen bonds decreased, while the number of OH groups with weak hydrogen bonds increased. With the increase in potentization, the number of OH groups with broken hydrogen bonds showed a difference in the presence and absence of the medicine.The voltage measurements for ethanol show that, with succussion, the magnitude of voltage increased with the two medicines at lower potencies, but not at higher potency where the voltage is lower. Acidum benzoicum, which is acidic in nature, had higher voltage values (113mV, 130 mV and 118 mV at 6C, 30C and 200C, respectively), compared with Chininum purum, which is basic in nature (20 mV, 85 mV and 65 mV at 6C, 30C and 200C, respectively). Conclusion The experimental results indicate a correlation between the vibrational and electrical properties of the homeopathic medicines Acidum benzoicum and Chininum purum at different potencies.

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