CHF2CF2C(=O)Cl




























 









Chlorine


Nuclear Quadrupole Coupling Constants


in 2,2,3,3-Tetrafluoropropionyl Chloride



 








 








 








Calculation of the chlorine nqcc's in 2,2,3,3-tetrafluoropropionyl chloride was made on an approximate equilibrium structure derived by MP2/aug-cc-pVTZ optimization with empirically corrected bond lengths.  These calculated nqcc's are compared with the experimental values [1] in Table 1.  Structure parameters are given in Table 2, rotational constants in Table 3.


 








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.  The nqcc y-axis is chosen coincident with the inertia c-axis, these are perpendicular to the molecular symmetry plane.  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 experimental nqcc's).  RSD is the calibration residual standard deviation for the B1LYP/TZV(3df,2p) model for calculation of the chlorine nqcc's, which may be taken as an estimate of the uncertainty in the calculated coupling constants.

 








 








   







Table 1. Chlorine nqcc's in CHF2CF2C(=O)Cl (MHz).  Calculation was made on the approximate equilibrium structure.

   










Calc.
Expt. [1]
   







35Cl Xaa - 13.98 - 15.9784(73)



Xbb -
16.75
-
14.914(11)



Xcc
30.73
30.8927(83)



|Xab|
47.20
43.7(13)



|Xac|
19.09

22.9(29)



|Xbc|
  3.86
    -----


 







RMS

1.57 (7.6 %)





RSD
0.49 (1.1 %)



 







Xxx
43.53




Xyy
21.78




Xzz - 65.31




ETA - 0.333




Øz,CCl
  1.43



   





37Cl Xaa - 12.49 -
13.883(30)



Xbb -
11.70
-
10.382(44)



Xcc
24.19
24.265(32)



|Xab|
37.20
40.1(21)



|Xac|
15.16





|Xbc|
  2.80




 







RMS

1.11 (6.9 %)





RSD
0.44 (1.1 %)



 







 








 








 

Table 2.  CHF2CF2C(=O)Cl Selected structure parameters (Å and degrees).  Complete structure is given here in Z-matix format.
 


Parameter
 reapprox


C(2)C(1) 1.5306
C(1)C(8) 1.5407
C(1)=O 1.1830
C(8)Cl 1.7451
C(2)C(1)C(8) 113.45
C(1)C(8)=O 122.93
C(1)C(8)Cl 113.00

C(2)C(1)C(8)=O
- 96.66

C(2)C(1)C(8)Cl   82.37


 








 













Table 3.  CHF2CF2C(=O)35Cl Rotational Constants (MHz).  Calc is on the reapprox molecular structure.
 







  Calc.
  Expt. [1]







A
1692.5
1695.86317(49)


B
1218.0
1196.49785(47)


C
1092.0
1078.17743(39)



 









 









[1] W.C.Bailey, R.A.Powoski, and S.A.Cooke, J.Mol.Spectrosc. 273,1(2012).


 








 








CH3CH2C(=O)Cl
CF3CH2C(=O)Cl CF3CF2C(=O)Cl


 








 








Table of Contents




Molecules/Chlorine




 








 













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Last Modified 7 March 2012