CF3-CH2Cl
























 





 






Chlorine


Nuclear Quadrupole Coupling Constants

in 1-Chloro-2,2,2-Trifluoroethane


 








 








The microwave spectra of 1-chloro-2,2,2-trifluoroethane was first observed by Ogata et al. [1], and revisited under conditions of high resolution by Uriarte et al. [2].

 









Calculation of the chlorine nqcc's in 1-chloro-2,2,2-trifluoroethane (Cs) was made on a structure derived by MP2/aug-cc-pVTZ optimization (ropt), and on this same structure but with empirically corrected CCl, C-C, and CF bond lengths (~ re).  See here.  These calculated nqcc's are compared with experimental values [2] in Tables 1 and 2.  Structure parameters are given in Table 3, rotational constants in Table 4.


 








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.  The nqcc y-axis is chosen coincident with the inertia c-axis, these are perpendicular to the molecular symmetry plane.  (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 for the B1LYP/TZV(3df,2p) model for calculation of the chlorine efg's/nqcc's.

 








 








 
   








Table 1.  35Cl nqcc's in CF3-CH2Cl (MHz).  Calculation was made on the ropt and ~ re structures.
   










Calc. ropt 
Calc. ~ re
Expt. [2]

   








Xaa - 46.51 - 46.23 -
45.9651(10)


Xbb
  5.71
  5.57
  5.5538(11)


Xcc
40.80
40.66
40.4113(11)


|Xab|
52.36
52.24
52.103(13)


 








RMS

0.40 (1.3 %)

0.21 (0.69 %)




RSD
0.49 (1.1 %)
0.49 (1.1 %)



 







Xxx
38.10
37.98
37.917(12)


Xyy
40.80
40.66
40.4113(11)

Xzz - 78.90 - 78.64 -
78.329(12)


ETA
0.034
0.034
0.03184(15)


z,a
31.75
31.81
31.8462(29)


a,CCl
32.28
32.32



z,CCl
  0.53
  0.50



 








 








 








   








Table 2.  37Cl nqcc's in CF3-CH2Cl (MHz).  Calculation was made on the ropt and ~ re structures.
   










Calc. ropt 
Calc. ~ re
Expt. [2]

   








Xaa - 36.69 - 36.47 -
36.2658(16)


Xbb
  4.53
  4.42
  4.4144(19)


Xcc
32.16
32.05
31.8514(19)


|Xab|
41.25
41.16
41.106(69)


 








RMS

0.31 (1.3 %)

0.16 (0.67 %)




RSD
0.44 (1.1 %)
0.44 (1.1 %)



 







Xxx
30.03
29.93
29.937(62)


Xyy
32.16
32.05
31.8514(19)

Xzz - 62.19 - 61.98 -
61.789(62)


ETA
0.034
0.034
0.0310(10)


z,a
31.72
31.79
31.836(19)


a,CCl
32.26
32.29



z,CCl
  0.53
  0.50



 








 








 












Table 3.  CF3-CH2Cl.  Heavy atom structure parameters ( and degrees).  Complete structures are given here in Z-matrix (G03 input file) format.
 



   ropt    ~ re
 

CCl 1.7668 1.7636
C-C 1.5110 1.5094
CF(8) 1.3452 1.3391
CF(6,7) 1.3362 1.3302
CCCl 111.24 111.24
CCF(8) 108.71 108.71
CCF(6,7) 112.23 112.23
ClCCF(6,7) 60.92 60.92
 





 













Table 4.  CF3-CH235Cl.  Rotational Constants (MHz).
 





  ropt   ~ re   Expt [2]






A 5327.3 5368.6 5332.845695(46)

B 1808.1 1816.7 1803.398752(16)

C 1789.8 1797.8 1784.676242(16)


 








 








[1] T.Ogata, K.Koike, and H.Suzuki, J.Mol.Struct. 144,1(1986): Xaa = - 45.94(50), Xbb = 5.68(40),  and Xcc = 40.26(50) MHz, for 35Cl.


[2] I.Uriarte, Z.Kisiel, E.Białkowska-Jaworska, L.Pszczłkowski, P.Ecija, F.J.Basterretxea, and  E.J.Cocinero, J.Mol.Spectrosc. 337,37(2017).


 









Ibid., 70th International Symposium on Molecular Spectroscopy, Abstract RF11, Champaign-Urbana, 2015.

 









 








CH3Cl CH3CH2Cl CH2ClCHF2 CH3CCl3

CF2ClCH3 CF2ClCHF2 CF2ClCH2F CF2ClCF3

CF3Cl CH2ClCH2F



 








 








Table of Contents




Molecules/Chlorine




 








 













CF3CH2Cl.html






Last Modified 21 Feb 2017