HON=O
















 








Nitrogen


Nuclear Quadrupole Coupling Constants


in Nitrous Acid


 








 








Nitrogen nqcc's and substitution molecular structures were determined by Cox et al. [1] for both cis and trans conformers of nitrous acid.


 


 





Calculation was made of the nitrogen nqcc's in these conformers on the rs structures.  Calculated and experimental nqcc's are compared in Tables 1 and 2.  Structure parameters are given in Table 3,













cis-HON=O


trans-HON=O



























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.  ETA = (Xxx - Xyy)/Xzz.  (degrees) is the angle between its subscripted parameters.

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

 








 








   







Table 1.  Nitrogen nqcc's in cis-HON=O (MHz).  Calculation was made on rs structure.

 









Calc.
Expt. [1]
   







14N Xaa
2.091

2.05(8)



Xbb -
5.928
-
5.83(7)



Xcc
3.837

3.78(7)



Xab
1.634




 







RMS
0.070 (1.8 %)





RSD
0.030 (1.3 %)



 






  Xxx
2.413





Xyy
3.837





Xzz -
6.250





ETA
0.228





z,a
101.11





a,bi*
  83.78





z,bi*
  17.33




 







 









* "bi" is bisector of ON=O angle.

 









 









   







Table 2.  Nitrogen nqcc's in trans-HON=O (MHz).  Calculation was made on rs structure.

 









Calc.
Expt. [1]
   







14N Xaa
1.796

1.73(7)



Xbb -
5.341
-
5.28(6)



Xcc
3.545

3.55(6)



Xab
2.147




 







RMS
0.052 (1.5 %)




RSD
0.030 (1.3 %)



 






  Xxx
2.392





Xyy
3.545





Xzz -
5.937





ETA
0.194





z,a
74.48





a,bi*
94.46





z,bi*
19.98




 







 









* "bi" is bisector of ON=O angle.


 









 













Table 3.  Nitrous Acid.  Structure Parameters [1] ( and degrees).
 





 cis
trans







HO
0.982
0.958


ON
1.392
1.432


N=O
1.185
1.170


HON
104.0
102.1


ON=O
113.6
110.7




 









 









[1] A.P.Cox, A.H.Brittain, and D.J.Finnigan, Trans. Faraday Soc. 67,2179(1971).


 









 








Methy Nitrite
Ethyl Nitrite
tert-Butyl Nitrite




 








 








Table of Contents





Molecules/Nitrogen




 








 













HONO.html






Last Modified 3 Jan 2016