NC5H4-CH=CH2




























 








Nitrogen

Nuclear Quadrupole Coupling Constants


in 4-Vinylpyridine


 








 








 

 





The nitrogen nqcc tensor in 4-vinylpyridine was calculated here on an ropt molecular structure given by B3P86/6-31G(3d,3p) optimization, assuming a plane of symmetry coincident with the plane of the ring [1].  These calculated nqcc's are given in Table 1.  Structure parameters in Z-matrix format are given in Table 2, rotational constants in Table 3.

 








In Table 1, subscripts a,b,c refer to the principal axes of the inertia tensor, subscripts x,y,z to the principal axes of the nqcc tensor.  The nqcc y-axis is chosen coincident with the inertial c-axis, these are perpendicular to the symmetry plane of the molecule.  Ø (degrees) is the angle between its subscripted parameters.  ETA = (Xxx - Xyy)/Xzz.

 








RMS is the root mean square difference between calculated and experimental diagonal nqcc's.  RSD is the calibration residual standard deviation for the B3PW91/6-311+(df,pd) model for calculation of the efg's/nqcc's.

 








 








   






Table 1.  Nitrogen nqcc's in 4-Vinylpyridine (MHz).  Calculation was made on the B3P86/6-31G(3d,3p) ropt structure.
   









Calc.
Expt.
   






14N Xaa -
 4.642




Xbb
1.269




Xcc
3.373




|Xab|
1.068



 







RMS






RSD
0.030 (1.3 %)



 






  Xxx
1.456




Xyy
3.373




Xzz -
 4.830




ETA
0.397




Øz,a
9.93




Øa,bi *
9.73




Øz,bi
0.20



 







 








* Angle between the a-axis and the bisector ("bi") of the CNC angle.

 







 
 



Table 2.  4-Vinylpyridine.  Molecular structure parameters, ropt (Å and degrees).






 C
 C,1,B1
 C,2,B2,1,A1
 C,3,B3,2,A2,1,D1,0
 C,4,B4,3,A3,2,D2,0
 N,1,B5,2,A4,3,D3,0
 H,1,B6,6,A5,5,D4,0
 H,2,B7,1,A6,6,D5,0
 H,4,B8,3,A7,2,D6,0
 H,5,B9,4,A8,3,D7,0
 C,3,B10,2,A9,1,D8,0
 C,11,B11,3,A10,2,D9,0
 H,11,B12,3,A11,2,D10,0
 H,12,B13,11,A12,3,D11,0
 H,12,B14,11,A13,3,D12,0










 B1=1.38872668
 B2=1.39688009
 B3=1.39862485
 B4=1.38553664
 B5=1.33216614
 B6=1.08787175
 B7=1.08555816
 B8=1.08424036
 B9=1.08775568
 B10=1.46484814
 B11=1.33329171
 B12=1.08811877
 B13=1.08394687
 B14=1.08516398
  A1=119.64659597
 A2=116.50466077
 A3=119.32825183
 A4=123.87584893
 A5=116.05712983
 A6=120.04809535
 A7=121.2385538
 A8=119.89953899
 A9=119.6321603
 A10=126.57865505
 A11=114.83702123
 A12=120.91318034
 A13=122.56574955
  D1=0.
 D2=0.
 D3=0.
 D4=180.
 D5=180.
 D6=180.
 D7=180.
 D8=180.
 D9=180.
 D10=0.
 D11=180.
 D12=0.








 








 













Table 3.  4-Vinylpyridine.  Rotational constants (MHz).
 





Calc/ropt   Expt [1]






A
   5494
 5436.82(11)

B
   1550
 1544.397(2)

C
   1209
 1204.700(1)


 








 








[1] W.M.Ralowski, P.J.Mjöberg, and S.O.Ljunggren, JACS 98,6897(1976): "The molecule has been shown to be planar in the ground state"

 








 








Pyridine4-Methylpyridine 4-Chlorostyrene


4-Pyridine Carbaldehyde






 








 








Table of Contents





Molecules/Nitrogen




 








 













4vinylpyridine.html






Last Modified 12 June 2014