o-Cl-C6H4-C(=O)H















 








 









Chlorine


Nuclear Quadrupole Coupling Constants

in ortho-Chlorobenzaldehyde


 








 








 


 





Calculation of chlorine nuclear quadrupole coupling constant tensors in ortho-chlorobenzaldehyde was made here on ropt molecular structures given by B3P86/6-31G(3d,3p) optimization (assuming Cs symmetry) of each of the two conformers shown below:


 








cis


trans


At the



B1LYP/TZV(3df,2p)

level of theory,

Etrans < Ecis

by 10.6 kJ/mol





 









 









Calculated nqcc tensors are given in Tables 1 and 2, rotational constants and dipole moments in Table 3.  Structure parameters are given here in Z-matrix format.


 









In Tables 1 and 2, 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.  (degrees) is the angle between its subscripted parameters.  ETA = (Xxx - Xyy)/Xzz.

RSD is the calibration residual standard deviation of the B1LYP/TZV(3df,2p) model for calculation of the efg's/nqcc's.

 








 








   







Table 1.  Chlorine nqcc's in cis ortho-Chlorobenzaldehyde (MHz).  Calculation was made on B3P86/6-31G(3d,3p) ropt structure.

   










Calc

Expt

   







35Cl Xaa -
43.17





Xbb
13.55





Xcc
29.61





|Xab|
52.75




 







RSD
0.49 (1.1 %)



 







Xxx
45.08





Xyy
29.61




Xzz -
74.70





ETA
-
0.207





z,a

30.87





a,CCl
28.56





z,CCl
  2.30




 






37Cl Xaa -
39.29





Xaa
12.95





Xaa
23.34





|Xab|
40.27




 








RSD

0.44 (1.1 %)



 








 








 









   







Table 2.  Chlorine nqcc's in trans ortho-Chlorobenzaldehyde (MHz).  Calculation was made on B3P86/6-31G(3d,3p) ropt structure.

   










Calc

Expt

   







35Cl Xaa -
71.14





Xbb
38.69





Xcc
32.45





|Xab|
11.97




 







RSD
0.49 (1.1 %)


 







Xxx
39.98





Xyy
32.45




Xzz -
74.43





ETA
-
0.104





z,a

  6.15





a,CCl
  4.59





z,CCl
  1.55




 






37Cl Xaa -
55.93





Xaa
30.36





Xaa
25.58





|Xab|
10.03




 








RSD

0.44 (1.1 %)



 








 









 








 




Table 3.  ortho-Chlorobenzaldehyde, 35Cl species.  Rotational Constants (MHz) and Electric dipole moments * (D).

 



cis
  ropt   Expt.





A
2156.9


B
1318.8


C
  818.4


|a|
  4.38


|b|   0.10


 



trans






A
1579.9


B
1550.9


C
  782.6


|a|   1.20


|b|   3.16






B1LYP/TZV(3df,2p) dipole moments calculated on B3P86/6-31G(3d,3p) structures.



 








 









 








Chlorobenzene
m-Chlorobenzaldehyde
o-Chlorobenzonitrile

1,2-Dichlorobenzene
1,2-Chlorofluorobenzene o-Chlorotoluene


 









 









Table of Contents




Molecules/Chlorine




 








 













2Chlorobenzaldehyde.html






Last Modified 26 Nov 2013