F2C-CCl=ClC-CF2

































 








Chlorine


Nuclear Quadrupole Coupling Constants

in 1,2-Dichlorotetrafluorocyclobutene


 








 








 








Calculation of the nitrogen nqcc's in 1,2-dichlorotetrafluorocyclobutene was made on the ro and rs/ro molecular structure of Van Wynsberghe et al. [1].  These are compared with the experimental nqcc's [1,2] in Tables 1 - 5.  Structure parameters are given in Table 6.

 








In Tables 1 - 4, subscripts a,b,c refer to the principal axes of the inertia tensor, subscripts 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 plane of the molecule.  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 (percent of the average absolute experimental nqcc).  RSD is the residual standard deviation of calibation of the  B1LYP/TZV(3df,2p) model for calculation of the nqcc's.

 








 








   








Table 1.  35Cl nqcc's in F2C-C35Cl=35ClC-CF2 (MHz).  Calcuation was made on the ro and rs/ro molecular structures [1].
   

 








Calc. ro
Calc. rs/ro
Expt. [1]
   

 






Xaa - 17.34 - 17.78 - 17.635(6)

Xbb - 15.68 - 15.28 - 14.966 *

Xcc
33.02
33.06
32.602 *

|Xab|
59.72
59.89
57.887(27)

 
 





RMS
0.50 (2.3 %)
0.33 (1.5 %)



RSD
0.49 (1.1 %)
0.49 (1.1 %)





 





Xxx
43.22
43.38
41.602 **

Xyy
33.02
33.06
32.602

Xzz - 76.24 - 76.44 - 74.203

ETA - 0.134 - 0.135 - 0.121

Øz,a
44.60
44.40
44.34

Øa,CCl
44.80
44.62



Øz,CCl
 0.20
  0.22



 
 





   








* Derived here from Xaa and Xbb - Xcc = - 47.568(6) MHz.

** The principal values of the nqcc tensor were calculated here from the experimental data using Z. Kisiel's QDIAG.f.  (See http://info.ifpan.edu.pl/~kisiel/prospe.htm.)  

 








 








   








Table 2.  Cl nqcc's in F2C-C35Cl=37ClC-CF2 (MHz).  Calcuation was made on the ro and rs/ro molecular structures [1].
   

 








Calc. ro
Calc. rs/ro
Expt. [1]
   

 






Xaa(35Cl)
30.70
32.68
29.209(11)

Xbb - 63.72 - 65.74 - 61.810 *

Xcc
33.01
33.06
32.602 *

|Xab|
36.58
34.16
35.96(20)

 
 





RMS
1.41 (3.4 %)
3.04 (7.4 %)



RSD
0.49 (1.1 %)
0.49 (1.1 %)





 





Xaa(37Cl) - 51.01 - 52.90 - 49.975(13)

Xbb
24.99
26.85
24.280 **

Xcc
26.02
26.05
25.696 **

|Xab|
27.78
25.28
26.62(25)



 





RMS
0.75 (2.2 %)
2.26 (6.8 %)



RSD
0.44 (1.1 %)
0.44 (1.1 %)



 
 






 








* Derived here from Xaa and Xbb - Xcc = - 94.412(1) MHz.

** Derived here from Xaa and Xbb - Xcc = - 1.416(75) MHz.

 








  








   








Table 3.  37Cl nqcc's in F2C-C37Cl=37ClC-CF2 (MHz).  Calcuation was made on the ro and rs/ro molecular structures [1].
   

 








Calc. ro
Calc. rs/ro
Expt. [2]
   

 






Xaa - 13.67 - 14.01 - 14.89(3)

Xbb - 12.35 - 12.04 - 10.633(7)

Xcc
26.02
26.05
25.523(6)

|Xab|
47.07
47.20
55.4(1)

 
 





RMS
1.25 (7.4 %)
1.01 (5.9 %)



RSD
0.44 (1.1 %)
0.44 (1.1 %)



 
 






 









 









   








Table 4.  35Cl(5,6) nqcc's in F2C-C35Cl(5)=35Cl(6)13C-CF2 (MHz).  Calcuation was made on the ro and rs/ro molecular structures [1].
   

 








Calc. ro
Calc. rs/ro
Expt. [1]
   

 






Xaa(5) - 13.15 - 13.08 - 13.24(21)

Xbb - 19.86 - 19.98 - 19.22 *

Xcc
33.01
33.06
32.46 *

|Xab|
59.64
59.81
56.2(23)

 
 





RMS
0.49 (2.3 %)
0.56 (2.6 %)



RSD
0.49 (1.1 %)
0.49 (1.1 %)





 





Xaa(6) - 21.52 - 22.47 - 22.02(22)

Xbb - 11.49 - 10.59 - 10.70 **

Xcc
33.01
33.06
32.72 **

|Xab|
59.52
59.61
59.5(22)



 





RMS
0.56 (2.6 %)
0.33 (1.5 %)



RSD
0.44 (1.1 %)
0.44 (1.1 %)



 
 






 








* Derived here from Xaa and Xbb - Xcc = - 51.69(9) MHz.

** Derived here from Xaa and Xbb - Xcc = - 43.41(9) MHz.

 








 








   








Table 5.  35Cl nqcc's in F2C-C35Cl(5)=35Cl(6)C-13CF2 (MHz).  Calcuation was made on the ro and rs/ro molecular structures [1].
   

 








Calc. ro
Calc. rs/ro
Expt. [1]
   

 






Xaa(5) - 25.39 - 26.80 - 25.47(25)

Xbb
- 7.63
- 6.26
- 7.06 *

Xcc
33.02
33.06
32.54 *

|Xab|
59.07
59.02
59.1(8)

 
 





RMS
0.43 (2.0 %)
0.95 (4.4 %)



RSD
0.49 (1.1 %)
0.49 (1.1 %)





 





Xaa(6)
- 9.28
- 8.73
- 9.76(25)

Xbb - 23.74 - 24.33 - 22.91 **

Xcc
33.02
33.06
32.67 **

|Xab|
59.29
59.40
56.1(8)



 





RMS
0.59 (2.7 %)
1.04 (4.8 %)



RSD
0.49 (1.1 %)
0.49 (1.1 %)



 
 






 








* Derived here from Xaa and Xbb - Xcc = - 39.60(8) MHz.

** Derived here from Xaa and Xbb - Xcc = - 55.58(6) MHz.

 








 


Table 6.  1,2-Dichlorotetrafluorocyclobutene.  Structure parameters, ro and rs/ro ( and degrees).  The input file for calculation of the efg's was constructed with the rs atomic coordinates for the carbon and chlorine atoms, and ro coordinates of the fluorine atoms, given in Table 4 of ref. [1].
 


 
      ro    rs/ro 




C(1)C(2) 1.305(4) 1.311(15)
C(2)C(3) 1.495(3) 1.487(15)
C(3)C(4) 1.545(4) 1.551(15)
CCl 1.702(3) 1.705(15)
CF 1.354(2) 1.353
ClC=C 134.80(20) 134.62(60)
C=C-C   94.62(23)   94.63(60)
C-C-C   85.38(20)   85.37(60)
FC(3)C(2) 116.52(13) 116.59
FCF 106.38(19) 106.46
 



 








 








[1] A.W. Van Wynsberghe, S.A.Peebles, R.A.Peebles, and R.L.Kuczkowski, J.Phys.Chem. A 104,8702(2000).

[2] B.E.Long, E.A.Arsenault, L.Hansen, and S.A.Cooke, Abstract RE11, 69th International Symposium on Molecular Spectroscopy, Champaign-Urbana, Ill. 2014.

 









 








c-CHCl=CHCl CH2=CCl2 1,2-Dichloroperfluorocyclopentene



1,2-Dichloroperfluorocyclohexene






 








 








Table of Contents




Molecules/Chlorine




 








 













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Last Modified 5 Aug 2014