Red-, Blue-, or No-Shift in Hydrogen Bonds:  A Unified Explanation

Joseph, Jorly; Jemmis, Eluvathingal D.

doi:10.1021/ja067545z

Cited by 824 publications

(697 citation statements)

References 67 publications

Supporting

Mentioning

648

Contrasting

Unclassified

Order By: Relevance

“…It has now been realized that there is no fundamental difference between red-and blue-shifting hydrogen bonds [129]. Joseph and Jemmis [130] have provided a unified explanation for red-, blue-, and non-shifting hydrogen bonds based on the optimum X-H bond length in the X-HؒؒؒY hydrogen bond. They have shown that the X-HؒؒؒY energy minimum could occur at longer, equal, or shorter X-H distance compared to that in the non-hydrogenbonded XH.…”

Section: Spectroscopic Evidencementioning

confidence: 99%

Defining the hydrogen bond: An account (IUPAC Technical Report)

Arunan

Desiraju

Klein³

et al. 2011

Pure and Applied Chemistry

917

622

View full text Add to dashboard Cite

Abstract:The term "hydrogen bond" has been used in the literature for nearly a century now. While its importance has been realized by physicists, chemists, biologists, and material scientists, there has been a continual debate about what this term means. This debate has intensified following some important experimental results, especially in the last decade, which questioned the basis of the traditional view on hydrogen bonding. Most important among them are the direct experimental evidence for a partial covalent nature and the observation of a blue-shift in stretching frequency following X-HؒؒؒY hydrogen bond formation (XH being the hydrogen bond donor and Y being the hydrogen bond acceptor). Considering the recent experimental and theoretical advances, we have proposed a new definition of the hydrogen bond, which emphasizes the need for evidence. A list of criteria has been provided, and these can be used as evidence for the hydrogen bond formation. This list is followed by some characteristics that are observed in typical hydrogen-bonding environments.

show abstract

Section: Spectroscopic Evidencementioning

confidence: 99%

Defining the hydrogen bond: An account (IUPAC Technical Report)

Arunan

Desiraju

Klein³

et al. 2011

Pure and Applied Chemistry

917

622

View full text Add to dashboard Cite

show abstract

“…The formation of a hydrogen bond at C(2) leads to a change in the strength of the covalent C(2)-H bond, which in turn can be observed as a frequency shift of the corresponding vibrational mode. A red shift (i.e., a shift toward lower frequency or wavenumber) means a weakening of the bond, and a blue shift (i.e., a shift toward higher frequency or wavenumber) means strengthening [32].…”

Section: Vibrational Spectramentioning

confidence: 99%

Effects of C(2) Methylation on Thermal Behavior and Interionic Interactions in Imidazolium-Based Ionic Liquids with Highly Symmetric Anions

et al. 2018

View full text Add to dashboard Cite

Featured Application: The study aims at making a step towards the rational design of ionic liquids for specific applications. The key to this rational design is to fully understand the structure-property relationships. In other words, knowing the links between the behavior at the molecular and the macroscopic scale will enable to develop materials/fluids with optimal properties for a given application, e.g., a chemical process or an electrochemical device. Abstract:The chemical and physical properties of imidazolium-based ionic liquids are determined by the interactions between the counter-ions. The C(2) position plays an important role in these interactions, as it represents the predominant site for interionic hydrogen bonding. This study shows that the directional hydrogen bonds between highly symmetrical anions (iodide, tetrafluoroborate, hexafluorophosphate) and the C(2)-H group of the 1-methyl-3-propylimidazolium cation determine the molecular and macroscopic behavior in terms of the thermal properties. Upon replacing the C(2) proton by a methyl group, the anion repositions itself at the C(4)/(5) moiety, where it forms a new hydrogen bond, apparently with only one of the two CH groups. In addition, the larger the anion is in diameter, the more likely it will establish further interactions with other parts of the cation, such as the propyl chain.

show abstract

“…All of these bands of CNCs exhibited slight gradual red shift compared to the relative bands of cellulose. The associated red shift occurs because the water molecules form weaker hydrogen bonding with CNCs than cellulose [11], implying that the inter-molecular hydrogen bonding of CNCs molecules are stronger. The rates of increase in the intensities, which related to the adsorption of water molecules onto C1-OH, C2-OH, C3-OH and C6-OH positions of cellulose and CNCs are shown in Fig .4.…”

Section: Fig 2 Nir Spectrum Of (A) Cellulose (B) Cncs Before and Afmentioning

confidence: 99%

Comparison of Water Adsorption Properties of Cellulose and Cellulose Nanocrystals Studied by Near-Infrared Spectroscopy and Gravimetry

Angkuratipakorn

Singkhonrat

Christy

2017

KEM

View full text Add to dashboard Cite

Abstract. The adsorption properties of water molecules on cellulose and cellulose nanocrystals (CNCs), isolated from defatted rice bran (DRB) by 55% sulfuric acid hydrolysis under sonication were investigated. The powdered samples of cellulose and CNCs were analysed by using near infrared spectroscopy (NIR) and gravimetry at 38% and 55% humidities. Small amounts of samples were dried under vacuum at 120 o C and the NIR spectra of the dry samples and their spectra during the adsorption water molecules were measured by using an NIR spectrometer equipped with a transflectance accessory and a DTGS detector. The quantitative adsorption of water molecules by the samples was determined by gravimetry. Second and fourth derivative profiles of the NIR spectra were used in understanding the chemistry of adsorption of water molecules and the adsorption processes by the samples.The results show that the adsorption of water molecules by the cellulose samples gives rise to three prominent peaks that can be related to the water molecules engaged in hydrogen bonding with C2, C3 and C6-OH groups on the glucose units of the cellulose polymers. Furthermore, the cellulose nanocrystals adsorb twice as much of water as the cellulose polymer. It is also clear from the results that C2 and C3-OH groups in the glucose units adsorb water molecules at a faster rate than the C6-OH group and responsible for nearly 50% of the water adsorption.

show abstract

Red-, Blue-, or No-Shift in Hydrogen Bonds: A Unified Explanation

Cited by 824 publications

References 67 publications

Defining the hydrogen bond: An account (IUPAC Technical Report)

Defining the hydrogen bond: An account (IUPAC Technical Report)

Effects of C(2) Methylation on Thermal Behavior and Interionic Interactions in Imidazolium-Based Ionic Liquids with Highly Symmetric Anions

Comparison of Water Adsorption Properties of Cellulose and Cellulose Nanocrystals Studied by Near-Infrared Spectroscopy and Gravimetry

Contact Info

Product

Resources

About