CH2CClCN
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Chlorine and Nitrogen


Nuclear Quadrupole Coupling Constants


in 2-Chloroacrylonitrile


 







 
 
Calculation of the chlorine and nitrogen nqcc's in 2-chloroacrylonitrile was made on a molecular structure derived ab initio (see below).  These nqcc's are compared in Tables 1-4 with the experimental values of Kisiel and Pszczólkowski [1].  Structure parameters are given in Table 5.
 
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 inertia c-axis, these are perpendicular to the 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 nqcc's (percentage of average experimental nqcc).  RSD is the residual stand deviation of calibration of the model for calculation of the nqcc's.
 
 
   







Table 1.  35Cl nqcc's in CH2CClCN (MHz).
   










Calc.
Expt. [1]
   






35Cl Xaa - 33.21 - 31.8093(13)
Xbb - 1.39 - 3.1730(16)
Xcc 34.60 34.9823(16)
|Xab| 57.20 57.173(12)
 
RMS 1.33 (5.7 %)
RSD 0.49 (1.1 %)
 
Xxx 42.07 41.447(12)
Xyy 34.60 34.982(2)
Xzz - 76.67 - 76.430(12)
ETA - 0.097 - 0.0846(2)
Øz,a 37.23 37.970(2)
Øa,CCl 38.17 38.17 *
Øz,CCl   0.95   0.20 *
 
 
* Calculated here.
 
 
   







Table 2.  37Cl nqcc's in CH2CClCN (MHz).
   










Calc.
Expt. [1]
   






37Cl Xaa - 27.68 - 26.6099(25)
Xbb   0.40 - 0.9497(35)
Xcc 27.27 27.5596(35)
|Xab| 44.64 44.70(15)
 
RMS 1.01 (5.5 %)
RSD 0.44 (1.1 %)
 
Xxx 33.16 32.73(15)
Xyy 27.27 27.56(1)
Xzz - 60.43 - 60.29(15)
ETA - 0.097 - 0.086(2)
Øz,a 36.27 36.99
Øa,CCl 37.22 37.22 *
Øz,CCl   0.95   0.23 *
 
 
* Calculated here.
 
 
   







Table 3.  Nitrogen nqcc's in CH2C35ClCN (MHz).
   










Calc.
Expt. [1]
   






14N Xaa - 3.087 - 3.0609(19)
Xbb 1.073 1.0228(20)
Xcc 2.014 2.0380(20)
|Xab| 2.621 2.611(12)
 
RMS 0.036 (1.7 %)
RSD 0.030 (1.3 %)
 
Xxx 2.339 2.296(10)
Xyy 2.014 2.038(2)
Xzz - 4.352 - 4.336(10)
ETA - 0.075 - 0.060(2)
Øz,a 25.78 25.99(7)
Øa,CN 26.32 26.32 *
Øz,CN   0.54   0.33 *
 
   
* Calculated here.
 
 
   







Table 4.  Nitrogen nqcc's in CH2C37ClCN (MHz).
   










Calc.
Expt. [1]
   






14N Xaa - 2.998 - 2.9691(33)
Xbb 0.984 0.9329(33)
Xcc 2.014 2.0362(33)
|Xab| 2.689
 
RMS 0.036 (1.8 %)
RSD 0.030 (1.3 %)
 
 
 
Molecular Structure
 
The molecular structure was optimized at the MP2/6-311G(d,p) level of theory assuming Cs symmetry.  The optimized C=C, C-CN, and CN bond lengths were corrected using equations obtained from linear regression analyses of the data given in Tables VIII and IX of Ref.[2].   For the CCl bond, the structure was optimized at the MP2/6-311+G(2d,p) level and corrected by linear regression analysis of the data given in Table 4 of Ref.[3].  The CH bond lengths were corrected using r = 1.001 ropt, where ropt is obtained by MP2/6-31G(d,p) optimization [4].  Interatomic angles used in the calculation are those given by MP2/6-311+G(d,p) optimization.
 
Table 5. Structure parameters (Å and degrees).
Hc and Ht are with respect to Cl.  CN tilts away from Cl.
C(1)Cl 1.723
C=C 1.334
C=CCl 122.7
C(1)C 1.431
CN 1.158
C=CC 122.0
C(1)CN 179.8
C(2)Hc 1.080
C(2)Ht 1.081
CCHc 120.8
CCHt 119.7
 
 
[1] Z.Kisiel and L.Pszczólkowski, J.Mol.Spectrosc. 184,215(1997).
[2] J.Demaison, J.Cosléou, R.Bocquet, and A.G.Lesarri, J.Mol.Spectrosc. 167,400(1994).
[3] I.Merke, L.Poteau, G.Wlodarczak, A.Bouddou, and J.Demaison, J.Mol.Spectrosc. 177,232(1996).
[4] J.Demaison and G.Wlodarczak, Structural Chem. 5,57(1994).

 








 








CH2CHCN CH2C(CN)2 CH2CHCl CH2CCl2
 

 








Table of Contents



Molecules/Chlorine
Molecules/Nitrogen
 

 













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Last Modified 28 Sept 2005