Scalar coupling constants across the intramolecular NHN hydrogen bond of symmetrically and non-symmetrically substituted 6-aminofulvene-1-aldimines

2001 ◽  
Vol 39 (S1) ◽  
pp. S100-S108 ◽  
Author(s):  
Mariusz Pietrzak ◽  
Hans-Heinrich Limbach ◽  
Marta P�rez-Torralba ◽  
Dion�sia Sanz ◽  
Rosa Mar�a Claramunt ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Coupling Constants ◽  
Scalar Coupling

scholarly journals NMR Properties of the Cyanide Anion, a Quasisymmetric Two-Faced Hydrogen Bonding Acceptor

Symmetry ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1298
Author(s):  
Ilya G. Shenderovich ◽  
Gleb S. Denisov
Keyword(s):  
Hydrogen Bonding ◽  
Experimental Studies ◽  
Polarizable Continuum Model ◽  
Coupling Constants ◽  
Scalar Coupling ◽  
Cyanide Anion ◽  
Molecular Systems ◽  
Polarizable Continuum ◽  
Chemical Shieldings ◽  
Nmr Properties

The isotopically enriched cyanide anion, (13C≡15N)−, has a great potential as the NMR probe of non-covalent interactions. However, hydrogen cyanide is highly toxic and can decompose explosively. It is therefore desirable to be able to theoretically estimate any valuable results of certain experiments in advance in order to carry out experimental studies only for the most suitable molecular systems. We report the effect of hydrogen bonding on NMR properties of 15N≡13CH···X and 13C≡15NH···X hydrogen bonding complexes in solution, where X = 19F, 15N, and O=31P, calculated at the ωB97XD/def2tzvp and the polarizable continuum model (PCM) approximations. In many cases, the isotropic 13C and 15N chemical shieldings of the cyanide anion are not the most informative NMR properties of such complexes. Instead, the anisotropy of these chemical shieldings and the values of scalar coupling constants, including those across hydrogen bonds, can be used to characterize the geometry of such complexes in solids and solutions. 1J(15N13C) strongly correlates with the length of the N≡C bond.

scholarly journals THE CASE OF ASYMPTOTIC SUPERSYMMETRY

2013 ◽  
Vol 28 (14) ◽  
pp. 1350053 ◽  
Author(s):  
BRUCE L. SÁNCHEZ-VEGA ◽  
ILYA L. SHAPIRO
Keyword(s):  
Fixed Point ◽  
Renormalization Group ◽  
Gauge Coupling ◽  
High Energy ◽  
Systematic Investigation ◽  
Coupling Constants ◽  
Scalar Coupling ◽  
Asymptotic State ◽  
Stable Fixed Point ◽  
Scalar Couplings

We start systematic investigation for the possibility to have supersymmetry (SUSY) as an asymptotic state of the gauge theory in the high energy (UV) limit, due to the renormalization group running of coupling constants of the theory. The answer on whether this situation takes place or not, can be resolved by dealing with the running of the ratios between Yukawa and scalar couplings to the gauge coupling. The behavior of these ratios does not depend too much on whether gauge coupling is asymptotically free (AF) or not. It can be shown that the UV stable fixed point for the Yukawa coupling is not supersymmetric. Taking this into account, one can break down SUSY only in the scalar coupling sector. We consider two simplest examples of such breaking, namely N = 1 supersymmetric QED and QCD. In one of the cases one can construct an example of SUSY being restored in the UV regime.

Proton spin–spin coupling constants and intramolecular hydrogen bonding in bromine derivatives of 1,3-dihydroxybenzene

1976 ◽  
Vol 54 (14) ◽  
pp. 2228-2230 ◽  
Author(s):  
Ted Schaefer ◽  
J. Brian Rowbotham
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Proton Spin ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Hydroxyl Groups ◽  
Oh Groups ◽  
Spin Coupling Constants ◽  
Spin Spin Coupling ◽  
Derivatives Of

The conformational preferences in CCl4 solution at 32 °C of the hydroxyl groups in bromine derivatives of 1,3-dihydroxybenzene are deduced from the long-range spin–spin coupling constants between hydroxyl protons and ring protons over five bonds. Two hydroxyl groups hydrogen bond to the same bromine substituent in 2-bromo-1,3-dihydroxybenzene but prefer to hydrogen bond to different bromine substituents when available, as in 2,4-dibromo-1,3-dihydroxybenzene. When the OH groups can each choose between two ortho bromine atoms, as in 2,4,6-tribromoresorcinol, they apparently do so in a very nearly statistical manner except that they avoid hydrogen bonding to the common bromine atom.

scholarly journals Hydrogen Bond Studies. 125. A Deuteron Magnetic Resonance Study of Strontium Formate Dihydrate, Sr(HCOO)2 · 2D2O

1977 ◽  
Vol 32 (9) ◽  
pp. 1025-1029 ◽  
Author(s):  
Bo Berglund ◽  
Jörgen Tegenfeldt
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Magnetic Resonance ◽  
Electric Field Gradient ◽  
Room Temperature ◽  
Coupling Constants ◽  
Water Molecules ◽  
Magnetic Resonance Study ◽  
Quadrupole Coupling ◽  
Asymmetry Parameters

AbstractA room temperature (25 °C) deuteron magnetic resonance (DMR) study of a single crystal of Sr (HCOO)2 · 2 D2O is reported. Signals from all water molecules in the unit cell have been detected, and all four independent electric field gradient (EFG) tensors at the water deuterons have been determined from 409 quadrupole splittings. All spectra were recorded by rotating the crystal about one arbitrarily selected axis. The following quadrupole coupling constants and asymmetry parameters for the deuterons were obtained: 213.5(4), 189.3(4), 195.7(4) and 200.7(5) kHz and 0.117(3), 0.110(4), 0.116(4) and 0.098(3). The directions of the eigenvalues are qualitatively consistent with the crystal structure refined by Galigné 1; the result is in disagreement, however, with the earlier DMR study of Sr (DCOO)2 · 2 D2O (Reference 2).

Carbon magnetic resonance studies of some phenyl, furyl and thienyl organometallics. Some comments on carbon-metal scalar coupling

1974 ◽  
Vol 27 (2) ◽  
pp. 417 ◽  
Author(s):  
D Doddrell ◽  
KG Lewis ◽  
CE Mulquiney ◽  
W Adcock ◽  
W Kitching ◽  
...  
Keyword(s):  
Chemical Shift ◽  
Chemical Shifts ◽  
Substituent Effects ◽  
Coupling Constants ◽  
Scalar Coupling ◽  
Coupling Constant ◽  
Aryl Substituent ◽  
Magnetic Resonance Studies ◽  
Thienyl Group ◽  
13C Chemical Shift

13C chemical shift variations within a series of phenyl, furyl and thienyl Group IVB organometallics appear to be best understood in terms of the usual alkyl and aryl substituent effects on 13C chemical shifts and not variations in dπ ?pπ metal-aryl interactions. Large changes in 13C-metal scalar coupling constants have been observed suggesting that other factors besides the s-character of the carbon-metal bond is responsible in determining the coupling constant.

scholarly journals Determination of unresolved heteronuclear scalar coupling constants by J(up)-HSQMBC

2016 ◽  
Vol 268 ◽  
pp. 88-94 ◽  
Author(s):  
Simon Glanzer ◽  
Olaf Kunert ◽  
Klaus Zangger
Keyword(s):  
Coupling Constants ◽  
Scalar Coupling

High-resolution methods for the measurement of scalar coupling constants

2018 ◽  
Vol 109 ◽  
pp. 135-159 ◽  
Author(s):  
Yanqin Lin ◽  
Qing Zeng ◽  
Liangjie Lin ◽  
Zhong Chen ◽  
Peter B. Barker
Keyword(s):  
High Resolution ◽  
Coupling Constants ◽  
Scalar Coupling
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