(CH2)3CHCN




 






















 






 









Nitrogen


Nuclear Quadrupole Coupling Constants

in ax Cyclobutyl Cyanide


 








 








 








Calculation of the nitrogen nqcc tensor in axial cyclobutyl cyanide was made on an ropt structure obtained by MP2/6-311+G(3df,3pd) optimization with approximate equilibrium C-CN bond lengths.  These are compared with the experimental nqcc's [1] in Table 1.  Structure parameters 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; x,y,z to the principal axes of the nqcc tensor.   (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 (percentage of the average of the magnitudes of the experimental nqcc's).  RSD is the calibration residual standard deviation of the B3PW91/6-311+G(df,pd) model for calculation of the nitrogen nqcc's.

 









 








   







Table 1.  Nitrogen nqcc's in ax Cyclobutyl Cyanide (MHz).  Calculation was made on the ropt structure.
 
 









Calc
Expt [1]
 
 






14N
Xaa - 2.825
- 2.8668(33)



Xbb
1.990

2.093(28)



Xcc
0.835

0.773(28)



|Xac|
2.956





 






RMS
0.074 (3.9 %)




RSD
0.030 (1.3 %)





 






Xxx
2.181





Xyy
1.990




Xzz -
4.171





ETA
0.0459





z,a
27.40





a,CN
27.06





z,CN
  0.35





 






 








 









 

Table 2.  ax Cyclobutyl Cyanide.  Heavy atom structure parameters, ropt ( and degrees).  Complete ropt structure is given here in Z-matrix format.

 




  ropt





C(1,3)C(4) 1.5550

C(4)C(12)
1.4550

C(12)N 1.1572

C(1)C(4)C(3)   87.31

C(4)C(12)N 180.00.

C(1)C(2)C(3)C(4)  -21.39



 








 








 



Table 3.  ax Cyclobutyl Cyanide.  Rotational constants (MHz).






ropt Expt [1]

 



A
7570.6
7591.81(48)

B
2734.8
2681.97882(34)

C
2575.1
2505.94126(32)

 





 









 









[1] Dissertation, Frohman, Daniel, "Fourier Transform Microwave Spectroscopy of van der Waals Complexes and Metal Containing Species" (2013).  Faculty advisor,  Stewart E. Novick.

 








 









Cyclobutyl Chloride
Cyclopropyl Cyanide
Cyclohexyl Cyanide


Cyclobutyl Cyanide, eq







 









 








Table of Contents




Molecules/Nitrogen




 








 













cButylCN.html






Last Modified 18 Oct 2018