C6BH6Cl































 









Boron and Chlorine


Nuclear Quadrupole Coupling Constants


in 1-Chloroborepin


 








 








Calculation of the boron and chlorine nqcc's in 1-chloroborepin was made on a molecular structure given by B3P86/6-31G(3d,3p) optimization, assuming C2V symmetry.  The planarity of the molecule was demonstrated by microwave measurement of the inertial defect by Larsen et al. [1].  Boron and nitrogen nqcc'c were subsequently measured by Pejlovas et al. [2].  Calculated and experimental 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, 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 of the model for calculation of the nqcc's:  B1LYP/6-31G(df,p) for boron, and B1LYP/TZV(3df,2p) for chlorine.

 








 








   







Table 1. Boron and Chlorine nqcc's in 11B species of 1-Chloroborepin (MHz).  Calculation was made on the B3P86/6-31G(3d,3p) optimized structure.  The a-axis is coincident with the B-Cl bond direction, the c-axis is perpendicular to the plane of the molecule.
   










Calc
Expt [2]

   







11B
Xaa - 0.171 -
0.147(15) *



Xbb - 2.868 -
2.987(13)



Xcc
3.039
3.133(13)



 







RMS

0.089 (4.2 %)




  RSD
0.046 (2.1 %)




 





35Cl
Xaa - 38.02 -
36.381(22)  **



Xbb
28.92
27.739(32)


  Xcc
  9.10
  8.643(32)



 







RMS

1.20 (4.9 %)





RSD
0.49 (1.1 %)



   





37Cl
Xaa - 29.96 -
29.000(22) ***



Xbb
22.79 -
22.100(46 )



Xcc
  7.17
  6.900(46 )



 






  RMS

0.70 (3.6 %)





RSD
0.44 (1.1 %)




 







 








* Derived here from experimental 1.5Xaa = -0.220(22) and 0.25(Xbb - Xcc) = -1.5300(99) MHz.


** Derived here from experimental 1.5Xaa = -54.572(33) and 0.25(Xbb - Xcc) = 4.7740(79) MHz.

*** Derived here from experimental 1.5Xaa = -43.500(33) and 0.25(Xbb - Xcc) = 3.800(10) MHz.

 









 









   







Table 2. Boron and Chlorine nqcc's in 10B, 35Cl species of 1-Chloroborepin (MHz).  Calculation was made on the B3P86/6-31G(3d,3p) optimized structure.  The a-axis is coincident with the B-Cl bond direction, the c-axis is perpendicular to the plane of the molecule.
   










Calc
Expt [2]



 





10B
Xaa - 0.354 -
0.263(29) *



Xbb - 5.948 -
6.283(77)


  Xcc
6.302
6.545(77)



 







RMS

0.250 (5.7 %)




  RSD
0.102 (2.1 %)




 





35Cl
Xaa -
38.02 -
36.630(22) **



Xbb
28.92
27.889(42)


Xcc
  9.10
  8.741(42)



 







RMS

1.02 (4.2 %)





RSD

0.49 (1.1 %)




 







 









* Derived here from experimental 1.5Xaa = -0.394(43) and 0.25(Xbb - Xcc) = -3.207(18) MHz.

** Derived here from experimental 1.5Xaa = -54.945(33) and 0.25(Xbb - Xcc) = 4.7870(88) MHz.

 














Table 3. 1-Chloroborepin.  Molecular structure parameters, ropt ( and degrees).

 



BC(2) 1.5168 C(7)BC(2) 125.62

C(2)C(3) 1.3675 BC(2)C(3) 127.72

C(3)C(4) 1.4204 C(2)C(3)C(4) 129.36

C(4)C(5) 1.3683 C(3)C(4)C(5) 130.10

BCl 1.7922 BC(2)H 117.42

C(2)H 1.0893 C(2)C(3)H 116.92

C(3)H 1.0892 C(3)C(4)H 114.64

C(4)H 1.0873



 








 







 





Table 4. 1-Chloroborepin, 11B, 35Cl species.  Rotational Constants, ropt (MHz).
 




 
Calc. ropt Expt. [2]







A 3530.9 3490.905(35)


B 1158.9 1159.38520(79)


C   872.5   870.59492(56)


 








 








[1] N.W.Larsen, S.R.Hansen, and T.Pedersen, J.Mol.Struct. 780-781,317(2006).

[2] A.M.Pejlovas, Z.Zhou, A.J.Ashe, and S.G.Kukolich, J.Phys.Chem. A 122(6),1542(2018).

 









 








BH2Cl BCl3 BF2Cl


Borepin BHCl2



 








 








Table of Contents




Molecules/Boron




Molecules/Chlorine




 








 













1ClBorepin.html






Last Modified 28 Jan 2018