F2C6H4
























 












 









Deuterium


Nuclear Quadrupole Coupling Constants

in 1,2-Difluorobenzene, 4d

 








 








 

 





Calculation of the deuterium nqcc tensors in 1,2-difluorobenzene, 4d was made here on an ropt molecular structure given by B3P86/6-31G(3d,3p) optimization.  These are compared with the experimental nqcc's [1] in Table 1.  Structure parameters are given in Table 2, rotational constants in Table 3, and centrifugal distortion constants in Table 4.

 








In Table 1, 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 nqcc's (percentage of the average of the magnitudes of the experimental nqcc's).  RSD is the calibration residual standard deviation of the B3LYP/6-31G(df,3p) model for calculation of deterium efg's/nqcc's.

 








 








   







Table 1. D nqcc's in 1,2-Difluorobenzene, 4d (kHz).  Calculation was made on B3P86/6-31G(3d,3p) ropt molecular structure.
   











Calc
Expt [1]
   







2H
Xaa
129.9
131.1(41) *



Xbb
- 29.1
- 51.(7) *



Xcc -
 100.8
- 80.(7) *



|Xab|
114.3



 









RMS 17.5 (20.0 %)
  



RSD   1.1 (0.86 %)


 









Xxx
- 88.8





Xyy -
 100.8





Xzz
189.6





ETA
0.0632





Øz,a
27.58





Øa,CD
27.61





Øz,CD
  0.03



 








 








* Calculated here from experimental 1.5Xaa = 0.1967(62) and 0.25(Xbb - Xcc) = 0.0072(34) MHz [1].

 







 
 

Table 2.  1,2-Difluorobenzene molecular structure parameters, ropt = B3P86/6-31G(3d,3p) optimized structure (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
 C,1,B5,2,A4,3,D3,0
 H,1,B6,6,A5,5,D4,0
 H,2,B7,1,A6,6,D5,0
 F,3,B8,2,A7,1,D6,0
 F,4,B9,3,A8,2,D7,0
 H,5,B10,4,A9,3,D8,0
 H,6,B11,1,A10,2,D9,0    <--- D


 B1=1.39095005
 B2=1.38328634
 B3=1.3897015
 B4=1.38328634
 B5=1.38997498
 B6=1.0838955
 B7=1.08388232
 B8=1.33609963
 B9=1.33609963
 B10=1.08388232
 B11=1.0838955
 A1=119.22486321
 A2=120.48365672
 A3=120.48365672
 A4=120.29148007
 A5=120.20806276
 A6=122.0634699
 A7=120.48149724
 A8=119.03484604
 A9=118.71166689
 A10=120.20806276
 D1=0.
 D2=0.
 D3=0.
 D4=180.
 D5=180.
 D6=180.
 D7=180.
 D8=180.
 D9=180.






 














Table 3.  1,2-Difluorobenzene rotational constants (MHz).  ropt = B3P86/6-31G(3d,3p) optimized structure.
 





 

 ropt     Expt [1]








A
 3251.6
 3234.83167(92)



B
 2156.2
 2147.68666(57)



C
 1296.5
 1290.58578(57)


 




 














Table 4.  1,2-Difluorobenzene.  Quartic Centrifugal Distortion Constants (kHz).  Calc = B3LYP/cc-pVTZ.
 





 

  Calc    Expt [1]








D_J
 0.0607 0.0794(302)



D_JK
 0.119



D_K
 0.567


 
 d_1
 - 0.0260
d_2 - 0.00676
 

 
 

[1] M.Sun, B.Sargus, S.J.Carey, and S.G.Kukolich, Abstract RK11, 68th International Symposium on Molecular Spectroscopy, June 17-21, 2013.

 








 








Monofluorobenzene
 Benzene


 








 








Table of Contents




Molecules/Deuterium




 








 













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Last Modified 7 July 2013