2-Pyridone


















 




 








Nitrogen and Deuterium

Nuclear Quadrupole Coupling Constants

in 2-Pyridone

 








 








 








Nitrogen and Deuterium (N-D) nqcc's in 2-pyridone were determined by Tanjaroon et al. [1].

 








Calculation of the nqcc's was made here on a molecular structure derived by B3P86/6-31G(d,p) optimization.  Calculated and experimental nqcc's are compared in Tables 1 - 3.  Structure parameters are given in Table 4, rotational constants in Table 5.

 








In Tables 1 - 3, subscripts a,b,c refer to the principal axes of the inertia tensor; x,y,z to the principal axes of the nqcc tensor.  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 (percentage of the average of the magnitudes of the experimental nqcc's).  RSD is the calibration residual standard deviation of the (1) B3PW91/6-311+G(df,pd) and (2) B3PW91/6-311+G(d,p) models for calculation of nitrogen efg's/nqcc's; and of the B3LYP/6-31G(df,3p) model for calculation of the deuterium nqcc's.

 








 








   







Table 1.   14N nqcc's in 2-Pyridone (MHz).  Calculation was made on the B3P86/6-31G(d,p) optimized structure with both (1) B3PW91/6-311+G(df,pd) and (2) B3PW91/6-311+G(d,p) models.
   









Calc. (1)
Calc. (2)
Expt. [1]
   







Xaa
1.410
1.505
1.4962(38)

Xbb
1.204
1.259
1.2691(40)

Xcc - 2.615 - 2.764 - 2.7653(40)

|Xab|
0.073
0.056



 







RMS
0.107 (5.8 %)
0.008 (0.44 %)



RSD
0.030 (1.3 %)
0.086 (3.8 %)



 







Xxx
1.181
1.247



Xyy
1.434
1.517



Xzz - 2.615 - 2.764



ETA
0.096
0.098



Øz,c
   0
   0



 








 








a The principal z-axis of the nqcc tensor is perpendicular to the plane of the molecule (ab-plane).

 








  








   







Table 2.   14N nqcc's in 1-Deuterio-2-Pyridone (MHz).  Calculation was made on the B3P86/6-31G(d,p) optimized structure with both (1) B3PW91/6-311+G(df,pd) and (2) B3PW91/6-311+G(d,p) models.
   









Calc. (1)
Calc. (2)
Expt. [1]
   







Xaa
1.413
1.507
1.511(2)

Xbb
1.202
1.257
1.249(5)

Xcc - 2.615 - 2.764 - 2.759(5)

|Xab|
0.069
0.052



 







RMS
0.104 (5.7 %)
0.006 (0.32 %)



RSD
0.030 (1.3 %)
0.086 (3.8 %)



 








 








 








   







Table 3.   2H nqcc's in 1-Deuterio-2-Pyridone (kHz).  Calculation was made on (1) B3P86/6-31G(d,p) and (2) B3P86/6-31G(3d,3p) optimized structures.
   









Calc. (1)
Calc. (2)
Expt. [1]
   







Xaa
    2.1
    1.6 - 110(7)

Xbb
134.0
134.6
354(6)

Xcc - 136.1 - 136.2 - 244(6)

|Xab|
154.7
154.7



 







RMS
156 (66 %)
155 (66 %)



RSD
1.1 (0.86 %)
1.1 (0.86 %)



 







Xxx - 100.1 - 100.2



Xyy - 136.1 - 136.2



Xzz
236.2
236.5



ETA
0.152
0.152



Øz,a
56.54
56.64



Øa,NH
55.66
55.79



Øz,NH
  0.87
  0.85



 








 








 



Table 4.   2-Pyridone.  B3P86/6-31G(d,p) structure parameters (Å and degrees).
 









 C
 C,1,B1
 C,2,B2,1,A1
 C,3,B3,2,A2,1,D1,0
 C,4,B4,3,A3,2,D2,0
 N,1,B5,2,A4,3,D3,0
 H,3,B6,2,A5,1,D4,0
 H,1,B7,6,A6,5,D5,0
 H,2,B8,1,A7,6,D6,0
 H,4,B9,3,A8,2,D7,0
 O,5,B10,4,A9,3,D8,0
 H,6,B11,1,A10,2,D9,0



 B1=1.36106948
 B2=1.42286369
 B3=1.36319773
 B4=1.4483221
 B5=1.35873538
 B6=1.08669086
 B7=1.08419652
 B8=1.08195818
 B9=1.08341333
 B10=1.2243469
 B11=1.01145096
 A1=117.90194301
 A2=121.49306483
 A3=121.69751676
 A4=120.34087458
 A5=119.02079128
 A6=116.24946536
 A7=120.40843171
 A8=122.14142012
 A9=127.21849338
 A10=120.42931277
 D1=0.
 D2=0.
 D3=0.
 D4=180.
 D5=180.
 D6=180.
 D7=180.
 D8=180.
 D9=180.
 



The "tautomeric" hydrogen atom is rs = 2.124(1) Å from the center of mass of the molecule [1].  On the B3P86/6-31G(d,p) structure, it is also 2.124 Å.



 








 


Table 5.   2-Pyridone.  Rotational Constants (MHz).  Normal Species.
 



Calc = B3P86/6-31G(d,p) optimization.





  Calc
    Expt. [1]





A 5687. 5643.7580(18)

B 2791. 2793.46893(71)

C 1872. 1868.81993(51)


 








 








[1] C.Tanjaroon, R.Subramanian, C.Karunatilaka, and S.G.Kukolich, J.Phys.Chem. A 108,9531(2004).

 








L.D.Hatherley, R.D.Brown, P.D.Godfrey, A.P.Pierlot, W.Caminati, D.Damiani, S.Melendri, and L.B.Favero, J.Phys.Chem. 47,46(1993). 


 








 








Pyridine 2-Hydroxypyridine Quinoline

Pyrazole Imidazole Isoquinoline

 








 








Table of Contents




Molecules/Nitrogen




 








 













2Pyridone.html






Last Modified 30 June 2015