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NMR spin–spin coupling constants in hydrogen-bonded glycine clusters
(John Wiley & Sons Inc, 2018-08)
The influence of the hydrogen bond formation on the NMR spin–spin coupling constants (SSCC), including the Fermi contact (FC), the diamagnetic spin-orbit, the paramagnetic spin-orbit, and the spin dipole term, has been ...
NMR Spectroscopic Parameters of Molecular Systems with Strong Hydrogen Bonds
(American Chemical Society, 2010-07)
A series of closed H-bonded molecules that have (or not) delocalized bonds were studied. The dependence of both NMR spectroscopic parameters σ and J-couplings, and also the energy stability of such molecules with H-bond ...
Molecular orbital calculations of hydrogen bonding in ammonia - Formic acid system in the presence of electric fields
(2004)
The effects of electric fields on hydrogen bonding in ammonia-formic acid system, are examined with STO-3G and 6-31 G(d) wavefunctions. This system was used in a previous work to model hydrogen bonding in crystalline amino ...
Assessing parameter suitability for the strength evaluation of intramolecular resonance assisted hydrogen bonding in O-carbonyl hydroquinones
(MDPI AG, 2019)
© 2019 by the authors.Intramolecular hydrogen bond (IMHB) interactions have attracted considerable attention due to their central role in molecular structure, chemical reactivity, and interactions of biologically active ...
Hydrogenation of Multiple Bonds by Geminal Aminoborane-Based Frustrated Lewis Pairs
(Wiley-VCH, 2018-06-21)
The hydrogenation reaction of multiple bonds that is mediated by geminal aminoborane-based frustrated Lewis pairs (FLPs) has been explored by means of density functional theory calculations. It was found that the release ...
Effect of sodium ascorbate on composite resin bond strength to bleached teeth
(2014-01-01)
Objective: The objective of this study was to evaluate the effect of sodium ascorbate on resin composite bond strength. Methods: Forty human premolars were used, which were divided into 4 groups: C - (control) unbleached ...
Understanding the nature of bonding interactions in the carbonic acid dimers
(Springer, 2019-01)
Carbonic acid dimer, (CA)2, (H2CO3)2, helps to explain the existence of this acid as a stable species, different to a simple sum between carbon dioxide and water. Five distinct, well characterized types of intermolecular ...
Conformational analysis and intramolecular interactions in monosubstituted phenylboranes and phenylboronic acids
(Beilstein-institutFrankfurt Am MainAlemanha, 2013)
A DFT study of hydrogen storage in Zr(Cr0.5Ni0.5)2 Laves phase
(Pergamon-Elsevier Science Ltd, 2016-01)
Theoretical studies on the total energy, electronic structure and bond of Zr(Cr0.5Ni0.5) 2 intermetallic compound and its hydrides were performed using density functional calculations. The optimized c/a ratio was found in ...