g-CH2Cl-CH2F
























 









Chlorine


Nuclear Quadrupole Coupling Constants

in gauche-1-Chloro-2-Fluoroethane


 








 








 








Calculation of the chlorine nqcc's in gauche-1-chloro-2-fluoroethane was made on a structure given by MP2/aug-cc-pVTZ(G03) optimization (ropt), and on this structure but with empirically corrected CCl, C-C, and CF bond lengths (reemp).  See here.  Calculated and experimental [1] nqcc's are compared 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.  Øz,CCl (degrees) is the angle between the z-principal axis and the CCl bond direction.  ETA = (Xxx - Xyy)/Xzz.

RMS is the root mean square difference between calculated and experimental nqcc's (percentage of the average experimental nqcc).  RSD is the residual standard deviation of calibration of the B1LYP/TZV(3df,2p) model for calculation of the efg's/nqcc's.


 








 








 
   








Table 1.  35Cl nqcc's in g-CH2Cl-CH2F (MHz).  Calculation was made on the MP/aug-cc-pVTZ(G03) ropt and reemp structures.
   










Calc. ropt
Calc. reemp
Expt. [1] *

   








Xaa - 22.33 - 22.36 -
22.557(2)


Xbb
- 9.06
- 8.98
- 8.759(3)


Xcc
31.40
31.35
31.316(3)


Xab

52.68
52.55 -
52.2(4)


Xac -
16.90 -
16.84
15.7(19)


Xbc
16.16
16.09
16.3(5)


 







RMS

0.22 (1.1 %)

0.17 (0.8 %)




RSD

0.49 (1.1 %)

0.49 (1.1 %)












Xxx
35.98
35.89
34.7(16)


Xyy
37.99
37.90
38.5(11)


Xzz - 73.97 - 73.80 -
73.2(7)


ETA
0.028
0.027



Øz,CCl
  0.56
  0.57



 








 








* Calculated here from experimental 3/2Xaa, 1/4(Xbb - Xcc),  Xab,  Xac, and Xbc given in Table 3.2 of Ref. [1] using Kisiel's program QDIAG.f.


 








 








   








Table 2.  37Cl nqcc's in g-CH2Cl-CH2F (MHz).  Calculation was made on the MP/aug-cc-pVTZ(G03) ropt and reemp structures.
   










Calc. ropt
Calc. reemp
Expt. [1] *

   








Xaa - 18.11 - 18.14 -
18.281(3)


Xbb
- 6.69
- 6.63
- 6.456(3)


Xcc
24.80
24.76
24.737(3)


Xab

41.48
41.38 -
41.24(26)


Xac -
13.30 -
13.25
15.0(19)


Xbc
12.58
12.53
12.6(4)


 







RMS

0.17 (1.0 %)

0.13 (0.8 %)




RSD

0.44 (1.1 %)

0.44 (1.1 %)












Xxx
28.36
28.29
29.6(16)


Xyy
29.94
29.87
29.0(10)


Xzz - 58.30 - 58.16 -
58.6(7)


ETA
0.027
0.027



Øz,CCl
  0.56
  0.57



 








 








* See footnote Table 1.


 








   

Table 3.  g-CH2Cl-CH2F.  Heavy atom structure parameters (Å and degrees).  Complete structures are given here in Z-matrix Gaussian input format.
 




   ropt  reemp



CCl 1.7811 1.7778
C-C 1.5042 1.5029
CF 1.3861 1.3791
CCCl 111.49 111.49
CCF 110.20 110.20
FCCCl   67.72   67.72










 








 



Table 4.  g-CH235Cl -CH2F.  Rotational Constants (MHz).
   



      ropt     reemp     Expt. [1]






A 13582.7 13660.3 13606.5962(7)

B   3318.4   3330.1   3289.5214(4)

C   2898.2   2909.9   2876.6421(4)


 








 








[1] A.S.Dikkumbura, Masters Theses, Eastern Illinois University, 2016.  Faculty Advisor: R.A.Peebles.  Available for download at http://thekeep.elu.edu/theses/2443






















t-CH2Cl-CH2F CF3-CHCl2 CH3-CH2Cl CH2Cl-CHF2

CF2Cl-CH3 CF2Cl-CHF2 CF2Cl-CH2F CH3-CCl3

CF3Cl CH2Cl-CF3 CF2Cl-CF3 CH3Cl

 








 








Table of Contents




Molecules/Chlorine




 








 













gCH2ClCH2F.html






Created 9 Dec 2007






Modified 13 July 2016