




















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 r_{s} structures. Calculated and experimental nqcc's are compared in Tables 1 and 2. Structure parameters are
given in Table 3,














cisHON=O



transHON=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 = (X_{xx}  X_{yy})/X_{zz}. Ø (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 B3PW91/6311+G(df,pd) model for
calculation of the efg's/nqcc's. 































Table 1. Nitrogen nqcc's in cisHON=O (MHz). Calculation
was made on r_{s} structure. 













Calc. 

Expt. [1] 










^{14}N 
X_{aa} 

2.091


2.05(8)




X_{bb} 


5.928



5.83(7)




X_{cc} 

3.837


3.78(7)




X_{ab} 

1.634














RMS 

0.07_{0} (1.8 %)






RSD 

0.030 (1.3 %) 













X_{xx} 

2.413






X_{yy} 

3.837






X_{zz} 


6.250






ETA 

0.228






Ø_{z,a} 

101.11






Ø_{a,bi}* 

83.78






Ø_{z,bi}* 

17.33

























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
































Table 2. Nitrogen nqcc's in transHON=O (MHz). Calculation
was made on r_{s} structure. 













Calc. 

Expt. [1] 










^{14}N 
X_{aa} 

1.796


1.73(7)




X_{bb} 


5.341



5.28(6)




X_{cc} 

3.545


3.55(6)




X_{ab} 

2.147














RMS 

0.05_{2} (1.5 %)






RSD 

0.030 (1.3 %) 













X_{xx} 

2.392






X_{yy} 

3.545






X_{zz} 


5.937






ETA 

0.194






Ø_{z,a} 

74.48






Ø_{a,bi}* 

94.46






Ø_{z,bi}* 

19.98

























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




























Table 3. Nitrous Acid. Structure Parameters [1] (Â 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

tertButyl Nitrite

























Table of Contents







Molecules/Nitrogen 






























HONO.html 






Last
Modified 3 Jan 2016 









