Bromine-79 NQR for uncoordinated Br– ions in trans-[CoBr2(en)2][H5O2]Br2

1992 ◽  
Vol 47 (1-2) ◽  
pp. 129-133 ◽  
Author(s):  
A. Sasane ◽  
T. Matsuda ◽  
H. Honda ◽  
Y. Mori
Keyword(s):  
Hydrogen Bond ◽  
Point Charge ◽  
Room Temperature ◽  
Bond Formation ◽  
Relative Magnitude ◽  
Hydrogen Atoms ◽  
Point Charge Model ◽  
Hydrogen Bond Formation ◽  
Charge Model ◽  
In Trans

AbstractA single 79Br NQR line showing a frequency of 19.594 MHz at room temperature has been observed in the crystals of trans-[CoBr2(en)2] [ H5O2 ] Br2 and assigned to the Br - ions which are not coordinated to the central Co(III) atom. The electric field gradient (EFG) at the Br - nuclei arises from O-H • • • Br - hydrogen bond formation between the Br - ions and the terminal O - H hydrogen atoms in [ H5O2 ] + ions. The induced EFG is greater for the present bromine complex than that for the isostructural chlorine complex. A point charge model calculation explains well the relative magnitude of the EFG in the two crystals by introducing Sternheimer's antishielding factors for the halogen ions.

A point-charge representation of nonbonding electron pairs: model derived from the ability of the hydrogen bond to act as a probe of electron density

1989 ◽  
Vol 67 (11) ◽  
pp. 1683-1686 ◽  
Author(s):  
A. C. Legon ◽  
D. J. Millen
Keyword(s):  
Hydrogen Bond ◽  
Electrostatic Interaction ◽  
Point Charge ◽  
Angular Position ◽  
Electrostatic Charge ◽  
Electron Localization ◽  
Simple Point ◽  
Point Charge Model ◽  
Electron Pairs ◽  
Charge Model

A simple point-charge model is presented for some molecules B which assigns charges to atom centres and to nonbonding pairs, those for the latter placed at distances r along directions α as conventionally envisaged. The magnitude δ of the charge assigned to the nonbonding pairs is chosen so that the variation of the electrostatic interaction energy between B and HF with the angular position of HF agrees with that calculated on the basis of a more complete description (DMA) of the electrostatic charge distribution of B. The charges δ in the three molecules explored (B = H2O, H2CO, and H2S) prove to be only a few hundredths of an electron at distances r comparable with bond distances in B. Keywords: nonbonding pairs, point-charge model, hydrogen bond, Gillespie–Nyholm model, electron localization.

133Cs-Kernresonanz in Cs2 MX4-Kristallen

1968 ◽  
Vol 23 (12) ◽  
pp. 2029-2034 ◽  
Author(s):  
H. Hartmann ◽  
W. Strehlow ◽  
H. Haas
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Point Charge ◽  
Room Temperature ◽  
Unit Cell ◽  
Point Charge Model ◽  
Satisfactory Description ◽  
Charge Model ◽  
Quadrupole Coupling ◽  
Nuclear Quadrupole

The nuclear magnetic resonance of 133Cs (I=7/2) has been studied at room temperature in the isostructural compounds Cs2CuCl4, Cs2CuBr4, Cs2CoCl4 and Cs2ZnCl4. The nuclear quadrupole coupling tensors and the magnetic shift tensors have been determined at the two inequivalent sites of the unit cell for all complexes. A satisfactory description of the quadrupole coupling (νq ≲ 20 kc) with a point charge model is only possible by reducing the charge on the central ion of the MX4 tetrahedron to +1-1. Large isotropic shifts (up to 0.5%) with smaller anisotropic contributions have been found in the paramagnetic compounds. The diamagnetic Cs2ZnCl4 shows shift up to 0.03% relative to CsCl.

scholarly journals Hydrogen-bond dynamics for the extended simple point-charge model of water

2000 ◽  
Vol 62 (1) ◽  
pp. 579-587 ◽  
Author(s):  
Francis W. Starr ◽  
Johannes K. Nielsen ◽  
H. Eugene Stanley
Keyword(s):  
Hydrogen Bond ◽  
Point Charge ◽  
Simple Point ◽  
Point Charge Model ◽  
Charge Model ◽  
Hydrogen Bond Dynamics

Vapochromism induced by intermolecular electron transfer coupled with hydrogen-bond formation in zinc dithiolene complex

2020 ◽  
Vol 8 (42) ◽  
pp. 14939-14947
Author(s):  
So Yokomori ◽  
Shun Dekura ◽  
Tomoko Fujino ◽  
Mitsuaki Kawamura ◽  
Taisuke Ozaki ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Electron Transfer ◽  
Bond Formation ◽  
Intermolecular Electron Transfer ◽  
Hydrogen Bond Formation ◽  
Complex Crystal

A novel vapochromic mechanism by intermolecular electron transfer coupled with hydrogen-bond formation was realized in a zinc dithiolene complex crystal.

Diverse mechanisms of carbon-hydrogen bond formation through binuclear reductive elimination reactions

1982 ◽  
Vol 104 (2) ◽  
pp. 619-621 ◽  
Author(s):  
Mario J. Nappa ◽  
Roberto Santi ◽  
Steven P. Diefenbach ◽  
Jack Halpern
Keyword(s):  
Hydrogen Bond ◽  
Bond Formation ◽  
Reductive Elimination ◽  
Hydrogen Bond Formation ◽  
Elimination Reactions

Parametrizing a polarizable force field from ab initio data. I. The fluctuating point charge model

1999 ◽  
Vol 110 (2) ◽  
pp. 741-754 ◽  
Author(s):  
Jay L. Banks ◽  
George A. Kaminski ◽  
Ruhong Zhou ◽  
Daniel T. Mainz ◽  
B. J. Berne ◽  
...  
Keyword(s):  
Force Field ◽  
Ab Initio ◽  
Point Charge ◽  
Point Charge Model ◽  
Polarizable Force Field ◽  
Charge Model

Theoretical analysis of the (HNO)2, (HNO···HNS), and (HNS)2 dimers — A case of red and blue shifts of N–H stretching frequency

2010 ◽  
Vol 88 (8) ◽  
pp. 849-857 ◽  
Author(s):  
Nguyen Tien Trung ◽  
Tran Thanh Hue ◽  
Minh Tho Nguyen
Keyword(s):  
Hydrogen Bond ◽  
Quantum Chemical ◽  
Bond Formation ◽  
Blue Shift ◽  
Proton Donor ◽  
Basis Sets ◽  
Coupled Cluster ◽  
Hydrogen Bond Formation ◽  
Length Contraction ◽  
Moller Plesset

The hydrogen-bonded interactions in the simple (HNZ)2 dimers, with Z = O and S, were investigated using quantum chemical calculations with the second-order Møller–Plesset perturbation (MP2), coupled-cluster with single, double (CCSD), and triple excitations (CCSD(T)) methods in conjunction with the 6-311++G(2d,2p), aug-cc-pVDZ, and aug-cc-pVTZ basis sets. Six-membered cyclic structures were found to be stable complexes for the dimers (HNO)2, (HNS)2, and (HNO–HNS). The pair (HNS)2 has the largest complexation energy (–11 kJ/mol), and (HNO)2 the smallest one (–9 kJ/mol). A bond length contraction and a frequency blue shift of the N–H bond simultaneously occur upon hydrogen bond formation of the N–H···S type, which has rarely been observed before. The stronger the intramolecular hyperconjugation and the lower the polarization of the X–H bond involved as proton donor in the hydrogen bond, the more predominant is the formation of a blue-shifting hydrogen bond.

Internal Hydrogen Bond Formation in a syn-Hydroxyepoxide

Science ◽  
1982 ◽  
Vol 215 (4533) ◽  
pp. 695-696 ◽  
Author(s):  
J. P. GLUSKER ◽  
D. E. ZACHARIAS ◽  
D. L. WHALEN ◽  
S. FRIEDMAN ◽  
T. M. POHL
Keyword(s):  
Hydrogen Bond ◽  
Bond Formation ◽  
Hydrogen Bond Formation ◽  
Internal Hydrogen ◽  
Internal Hydrogen Bond
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