Polarographic and nuclear quadrupole resonance studies of some organic iodo compounds. II. The dependence of the half-step potential on the ionic character of the carbon-iodine bond

1968 ◽  
Vol 21 (6) ◽  
pp. 1403 ◽  
Author(s):  
RA Caldwell ◽  
S Hacobian
Keyword(s):  
Continuous Medium ◽  
Quadrupole Coupling Constant ◽  
Ionic Character ◽  
Coupling Constant ◽  
Step Potential ◽  
Nuclear Quadrupole Coupling Constant ◽  
Quadrupole Coupling ◽  
Quadrupole Resonance ◽  
Nuclear Quadrupole ◽  
Semi Empirical

Nuclear quadrupole coupling constant data are utilized to determine the ionic character of the carbon-iodine bond in a number of substituted iodobenzenes and related to the half-step potential of the corresponding substituted iodobenzene. A semi-empirical discussion using the Kirkwood-Westheimer relation for the interaction of poles in a continuous medium is given as the basis for such a relationship.

Temperature and Pressure Dependence of 209Bi Nuclear Quadrupole Resonance in BiCl3

1972 ◽  
Vol 50 (16) ◽  
pp. 2586-2590 ◽  
Author(s):  
G. C. Gillies ◽  
R. J. C. Brown
Keyword(s):  
Pressure Dependence ◽  
Room Temperature ◽  
Quadrupole Coupling Constant ◽  
Coupling Constant ◽  
Nuclear Quadrupole Coupling Constant ◽  
Quadrupole Coupling ◽  
Quadrupole Resonance ◽  
Temperature And Pressure ◽  
Nuclear Quadrupole ◽  
Crystal Volume

The temperature and pressure dependence of the 209Bi nuclear quadrupole coupling constant and asymmetry parameter in solid BiCl3 have been measured near room temperature. It is not possible to account for the results on the basis of the conventional theory in which the field gradient parameters depend only on the crystal volume.

Nuclear Quadrupole Coupling Constant and Conformational Studies

1986 ◽  
Vol 41 (1-2) ◽  
pp. 166-168
Author(s):  
V. Santhanam ◽  
J. Sobhanadri
Keyword(s):  
Molecular Conformation ◽  
Quadrupole Coupling Constant ◽  
Mean Value ◽  
Basis Sets ◽  
Slater Type Orbitals ◽  
Coupling Constant ◽  
Nuclear Quadrupole Coupling Constant ◽  
Quadrupole Coupling ◽  
Nuclear Quadrupole ◽  
Semi Empirical

A molecular conformation study on three 3-monosubstituted derivatives of propene has beencarried out by evaluating the EFG at the site of the halogen nucleus using a semi-empiricalLCAO-MO-SCF method. Calculations are performed on several conformers at INDO andCNDO level, using “sp” and “spd” valence basis sets, with Slater type orbitals as the basisfunctions. The results obtained for various conformers indicate that the nuclear quadrupolecoupling constant is practically independent of the orientation of the CH2X group (X = Cl, Brand I) (Figure 1). The mean value of e2 Qqzz/h (averaged over all conformers) in each systemmatches favourably with the experimental value, despite the severe approximations that areinherent in the semi-empirical theory as well as in its application in the evaluation of the EFG.

AB INITIO CALCULATIONS OF 14N NQR PARAMETERS AND 13C, 1H, AND 15N CHEMICAL SHIFTS INCLUDING A COMPARISON WITH EXPERIMENTAL NMR DATA FOR CYCLOTRISAZOBENZENE

2009 ◽  
Vol 08 (04) ◽  
pp. 647-656 ◽  
Author(s):  
NASSER ZAMAND ◽  
ALI R. ALIAKBAR ◽  
NASSER L. HADIPOUR
Keyword(s):  
Structural Changes ◽  
Chemical Shifts ◽  
Quadrupole Coupling Constant ◽  
Coupling Constant ◽  
Electron Pairs ◽  
Nuclear Quadrupole Coupling Constant ◽  
Quadrupole Coupling ◽  
Quadrupole Resonance ◽  
Nuclear Quadrupole ◽  
Experimental Values

Nuclear quadrupole coupling constant, χ, and asymmetry parameter, η, of 14 N nucleus and 13 C , 1 H , and 15 N chemical shifts for cyclotrisazobenzene at the level of B3LYP and MP2 methods have been studied using the Gaussian 98 suite of programs. Also, nuclear quadrupole resonance (NQR) frequencies (ν0, ν+, ν-) for 14 N have been calculated, thoroughly. The optimized structure of the compound was very similar to that given by the X-ray crystallographic data. The electric field gradient (EFG) calculation verified that the N = N bonds are highly localized in this molecule; therefore, electron-pairs of the nitrogen atoms remain nonbonding. The comparison of the calculated chemical shifts with the experimental values for cyclotrisazobenzene shows no significant structural changes in solution.

Weak Complexes of Dinitrogen: An Approach to the 14N-Nuclear Quadrupole Coupling Constant of Free N2

1992 ◽  
Vol 47 (1-2) ◽  
pp. 367-370 ◽  
Author(s):  
A. C. Legon ◽  
P. W. Fowler
Keyword(s):  
Ground States ◽  
Zero Point ◽  
Quadrupole Coupling Constant ◽  
Coupling Constants ◽  
Coupling Constant ◽  
Nuclear Quadrupole Coupling Constant ◽  
Quadrupole Coupling ◽  
Weak Complexes ◽  
Nuclear Quadrupole

AbstractThe 14N-nuclear quadrupole coupling constants χaa(14N<2>) and χaa(14N(1)) for the ground-states of the dimers 14N(2)14N(1) • • • HCCH and 14N(2)14N(1) • • • HC15N have been corrected for zero-point effects and for the electrical effects of the subunit HX to give two estimatesχ(14N) = -5.01 (13) and - 5.07 (8) MHz, respectively, for the coupling constant of the isolated 14N2 molecule

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