H2N-C6H4CN






















 




 









Nitrogen


Nuclear Quadrupole Coupling Constants


in 4-Aminobenzonitrile


 








 








 








Calculation was made of the amine and cyano N nqcc tensors in 4-Aminobenzonitrile (ABN) on ropt structures given by B3P86/6-31G(3d,3p) and by M06-2X/6-31G(3d,3p) optimizations.  These are compared with the experimental nqcc's of Betz et al. [1] in Table 1.  Structure parameters are given in Table 2.  Rotational constants are given in Table 3.

 








In Table 1, subscripts a,b,c refer to the principal axes of the inertia tensor.  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+G(df,pd) model for calculation of the efg's/nqcc's.

 








  








 








Table 1.  14N nqcc tensors in ABN (MHz).  Calculation was made on B3P86/6-31G(3d,3p) and M06-2X/6-31G(3d,3p) ropt structures, designated below Calc (1) and Calc (2) respectively.












Calc (1)
Calc (2)
Expt. [1]
 








Xaa (amino)
2.234
2.195
2.48(1)

Xbb
1.944
1.904
1.87(2)

Xcc - 4.178 -
 4.099
 - 4.352(2)

|Xac|
1.317
1.405












RMS
0.18 (6.2 %)
0.22 (7.6 %)



RSD
0.030 (1.3 %)
0.030 (1.3 %)












Xaa (cyano) - 4.119 -
 4.182
 - 4.138(9)

Xbb
2.453
2.465
2.40(2)

Xcc
1.666
1.716
1.74(2)

|Xac|
0.004
0.006












RMS
0.054 (1.9 %)
0.047 (1.7 %)



RSD
0.030 (1.3 %)
0.030 (1.3 %)












   








 








 


Table 2.  4-Aminobenzonitrile.  Selected structure parameters, ropt (Å and degrees).  Complete structures are given here in Z-matrix format.
 




Parameter B3P86M06-2X
 

C(1)C 1.42411.4341
CN 1.15921.1538
 

C(4)N 1.38041.3869
NH 1.00851.0092
C(4)NH 115.91115.00
HNH 112.60111.94
Inversion Angle *   38.05
  40.96
 

* Angle between the C(4)N direction and the bisector of the HNH angle.





 








 













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



 
B3P86
 M06-2X  Expt. [1]






A
 5613.9
  5612.0
 5581.0(4)

B
   994.9
    994.6
   990.3627(7)

C
   845.7
    845.5
   841.4827(6)


 








 








Benzonitrile (N-Dimethyl)aniline Aniline



(4-Dimethylamino)benzonitrile






 


















[1] T.Betz, S.Zinn, J.B.Graneek, and M.Schnell, J.Phys.Chem. A 118,5164(2014).

 








 








Table of Contents




Molecules/Nitrogen




 








 













4ABN.html






Last Modified 9 June 2014