2,6-Cl2-C5H3N



 

 








Nitrogen and Chlorine


Nuclear Quadrupole Coupling Constants


in 2,6-Dichloropyridine


 







 
 
Calculation was made of the nitrogen and chlorine nqcc tensors in 2,6-dichloropyridine on a molecular structure given by B3P86/6-31G(3d,3p) optimization.  These are shown in Tables 1 - 2.  Structure parameters are given in Table 3, atomic coordinates in Table 4, and rotational constants in Table 5.
 
In Tables 1 - 2, subscripts a,b,c refer to the principal axes of the inertia tensor; x,y,z to the principal axes of the nqcc tensor.  The nqcc y-axis is chosen coincident with the inertia c-axis, these are perpendicular to the molecular plane.  Ø (degrees) is the angle between its subscripted parameters.  ETA = (Xxx - Xyy)/Xzz.  RSD is the calibration residual standard deviation of the model for calculation of the nqcc's.
 

 







   







Table 1. Nitrogen nqcc's in 2,6-Dichloropyridine, normal species (MHz).  Calculation was made on the B3P86/6-31G(3d,3p) ropt structure.
 




Calc.
Expt.
   






14N Xaa 1.987
Xbb - 4.543
Xcc 2.556
ETA * 0.125
 
RSD 0.030 (1.3 %)
 
 
* ETA = (Xaa - Xcc)/Xbb = (Xxx - Xyy)/Xzz.
 
 
   







Table 2.  Chlorine nqcc's in 2,6-Dichloropyridine, normal species (MHz).  Calculation was made on the B3P86/6-31G(3d,3p) ropt structure.
   










Calc.
Expt.
   






35Cl Xaa - 39.65
Xbb   9.26
Xcc 30.40
Xab ± 50.99
 
RSD 0.49 (1.1 %)
   
  Xxx 41.35
Xyy 30.40
Xzz - 71.75
ETA - 0.153
Øz,a 32.19
Øa,CCl 32.07
Øz,CCl   0.12
 
 
 
 
Table 3.  2,6-Dichloropyridine.  Molecular structure parameters, ropt (Å and degrees).
 
N(1)C(2) 1.3204
C(2)C(3) 1.3902
C(3)C(4) 1.3897
C(2)Cl(2) 1.7331
C(3)H(3) 1.0819
C(4)H(4) 1.0846
C(6)N(1)C(2) 116.98
N(1)C(2)C(3) 124.60
C(2)C(3)C(4) 117.02
C(3)C(4)C(5) 119.78
N(1)C(2)Cl(2) 116.42
C(2)C(3)H(3) 120.69


 
 
Table 4.  2,6-Dichloropyridine.  Atomic coordinates, ropt.  Normal species.
 
 a (Å)  b (Å)
N(1) 0.0 0.6309
C(2,6) ± 1.1257 - 0.0592
C(3,5) ± 1.2006 - 1.4473
C(4) 0.0 - 2.1436
Cl(2,6) ± 2.5942 0.8611
H(3,5) ± 2.1594 - 1.9486
H(4) 0.0 - 3.2282
 
 

Table 5.  2,6-Dichloropyridine.  Rotational Constants (MHz).   Normal species.
 
Calc ropt        Expt.
A  2790.8
B    927.1
C    695.9


 
 

Pyridine 2-Chloropyridine 3-Chloropyridine

1,2-Dichlorobenzene 2,3-Dichloropyridine 2,4-Dichloropyridine
2,5-Dichloropyridine 3,4-Dichloropyridine 3,5-Dichloropyridine
2,6-Difluoropyridine 2,6-Dimethylpyridine 2,6-Dicyanopyridine
 
 

Table of Contents





Molecules/Nitrogen




Molecules/Chlorine



 

 













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Last Modified 15 Nov 2003