2-CN-C6H4OH



 





 








Nitrogen

Nuclear Quadrupole Coupling Constants


in ortho-Cyanophenol


 








 








 








Calculation of the 14N nqcc tensor in cis and trans conformers of o-cyanophenol was made here on molecular structures given by B3P86/6-31G(3d,3p) optimization (assuming Cs symmetry).  These calculated nqcc's are given in Tables 1 and 2.  Structure parameters are given in Table 3, rotational constants in Table 4.

 









cis



trans












Ecis < Etrans









 








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.  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 (percent of average of absolute experimental diagonal nqcc's).  RSD is the calibration residual standard deviation of the B3PW91/6-311+G(df,pd) model for calculation of the nqcc's, which may be taken as an estimate of the uncertainty in the calculated nqcc's.

 








 








   






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

 









Calc.
Expt. [1]
   






14N Xaa - 4.208 - 4.213(4)


Xbb
2.654
2.53(2)


Xcc
1.554
1.68(1)


|Xac|
0.428



 







RMS
0.105 (3.8 %)




RSD
0.030 (1.3 %)



 






  Xxx
2.680




Xyy
1.554




Xzz - 4.235




ETA - 0.266




Øz,a
3.56




Øa,CN
2.54




Øz,CN
1.02



 







 








 








   






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

 









Calc.
Expt.
   






14N Xaa - 4.112




Xbb
2.220




Xcc
1.892




|Xac|
0.852



 







RSD
0.030 (1.3 %)



 






  Xxx
2.333




Xyy
1.892




Xzz - 4.225




ETA - 0.104




Øz,a
7.53




Øa,CN
7.49




Øz,CN
0.04



 







 







 
 



Table 3.  o-Cyanophenol.  Selected structure parameters, ropt (Å and degrees).  Complete structures are given here in Z-matrix format.
 



 
cis-o-Cyanophenol




C(1)C(7) 1.4222

C(7)N 1.1603

C(1)C(7)N 175.25 *

C(2)C(1)C(6) 120.18

 

C(2)O 1.3450

OH 0.9677

C(2)OH 109.85

C(1)C(2)C(3) 119.30

 





* N tilts toward OH

 



 




trans-o-Cyanophenol




C(1)C(7) 1.4252

C(7)N 1.1582

C(1)C(7)N 178.44 **

C(2)C(1)C(6) 119.55

 

C(2)O 1.3487

OH 0.9625

C(2)OH 109.59

C(1)C(2)C(3) 119.50

 





** N tilts away from O



 








 


Table 4.  o-Cyanophenol.  Rotational Constants (MHz).
 



cis Calc. ropt  Expt. [1]





A 3083.4 3053.758(2)

B 1518.7 1511.2760(3)

C 1017.5 1010.7989(2)





trans Calc. ropt  Expt.





A 2995.8

B 1523.4

C 1009.9


 








 








[1] A.R.Conrad, N.Z.Barefoot, and M.J.Tubergen, PCCP 12,8350(2011);  64th Ohio State University Symposium on Molecular Spectroscopy, June 22-26, 2009.

 








 








Benzonitrile o-Tolunitrile o-Fluorobenzonitrile

m-Cyanophenol m-Tolunitrile m-Fluorobenzonitrile

p-Cyanophenol p-Tolunitrile p-Fluorobenzonitrile

 








 








Table of Contents





Molecules/Nitrogen




 








 













o_phenolCN.html






Last Modified 7 July 2009