3-CN-C5H4N



 

 








Nitrogen


Nuclear Quadrupole Coupling Constants


in 3-Cyanopyridine


 







 
 
Calculation was made here of the nitrogen nqcc's in 3-cyanopyridine on a structure optimized at the B3P86/6-31G(3d,3p) level of theory.  These nqcc's are shown in Tables 1 and 2.  Structure parameters are given in Table 3, atomic coordinates in Table 4, and rotational constants in Table 5.
 
In Tables 1 and 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 B3PW91/6-311+G(df,pd) model for calculation of the nqcc's.
 

 







   







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




Calc.
Expt.
   






14N Xaa - 0.056
Xbb - 3.438
Xcc 3.494
|Xab| 2.724
 
RSD 0.030 (1.3 %)
 
  Xxx 1.460
Xyy 3.494
Xzz - 4.954
ETA 0.410
Øz,a 60.92
Øa,bi 60.57
Øz,bi *   0.35
 
 
* The z-axis makes an angle of 0.35o with the external bisector ( 'bi' ) of the C(6)N(1)C(2) angle, and tilts toward C(2).
 
 
   







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










Calc.
Expt.
   






14N Xaa - 4.298
Xbb 2.337
Xcc 1.962
|Xab| 0.144
 
RSD 0.030 (1.3 %)
   
  Xxx 2.340
Xyy 1.962
Xzz - 4.302
ETA - 0.088
Øz,a 1.24
Øa,CN 1.32
Øz,CN 0.08
 
 
 
 
Table 3.  3-Cyanopyridine and Pyridine.  Molecular structure parameters, ropt (Å and degrees).
 
3-CN-Pyridine Pyridine
N(1)C(2) 1.3270 1.3336
C(2)C(3) 1.4006 1.3904
C(3)C(4) 1.3965 1.3885
C(4)C(5) 1.3845 1.3885
C(5)C(6) 1.3910 1.3904
C(6)N(1) 1.3342 1.3336
C(2)H(2) 1.0867 1.0880
C(4)H(4) 1.0839 1.0851
C(5)H(5) 1.0837 1.0845
C(6)H(6) 1.0873 1.0880
C(3)C(7) 1.4267
C(7)N(8) 1.1580
C(6)N(1)C(2) 117.51 117.03
N(1)C(2)C(3) 123.25 123.80
C(2)C(3)C(4) 118.58 118.44
C(3)C(4)C(5) 118.23 118.50
C(4)C(5)C(6) 118.63 118.44
C(5)C(6)N(1) 123.80 123.80
N(1)C(2)H(2) 116.97 115.94
C(2)C(3)C(7) 120.28
C(3)C(7)N(8) 179.84
C(3)C(4)H(4) 120.19 120.75
C(4)C(5)H(5) 120.98 121.35
C(5)C(6)H(6) 120.32 120.26


 
 
Table 4.  3-Cyanopyridine.  Atomic coordinates, ropt.
 
 a (Å)  b (Å)
N(1) - 1.5088 - 1.2062
C(2) - 0.1824 - 1.1643
C(3) 0.5482 0.0307
C(4) - 0.1497 1.2403
C(5) - 1.5336 1.1978
C(6) - 2.1622 - 0.0430
C(7) 1.9746 0.0017
N(8) 3.1323 - 0.0250
H(3) 0.3409 - 2.1167
H(4) 0.3894 2.1806
H(5) - 2.1197 2.1094
H(6) - 3.2476 - 0.1085
 
 

Table 5.  3-Cyanopyridine.  Rotational Constants (MHz). 
 
Calc ropt    Expt. [1]
A 5865.2 5823.01(5)
B 1578.9 1571.34(3)
C 1244.0 1237.17(3)


 
 
[1] R.G.Ford, J.Mol.Spectrosc. 58,178(1975).
 
 

Pyridine 3-Fluoropyridine 3-Chloropyridine

Benzonitrile 3-Bromopyridine 3-Methylpyridine
2-Cyanopyridine 4-Cyanopyridine
 
 

Table of Contents





Molecules/Nitrogen



 

 













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Last Modified 6 Dec 2003