ClFC=C=CH2
























 








 









Chlorine


Nuclear Quadrupole Coupling Constants

in 1-Chloro-1-Fluoroallene

 








 








 

 





35Cl nuclear quadrupole coupling constants in 1-chloro-1-fluoroallene were determined by Ogata [1].

 








Calculation of the nqcc's was made here on molecular structures given by PBE1PBE/6-31G(3d,3p) and MP2/aug-cc-pVTZ optimization, the latter with approximate equilibrium bond lengths.  These are compared with the experimental nqcc's [1] in Table 1.  Structure parameters are given in Table 2, rotational constants in Table 3.

 








In Table 1, 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.  Ø (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 of the B1LYP/TZV(3df,2p) model for calculation of the nqcc's.

 








 








   







Table 1.  35Cl nqcc's in 1-Chloro-1-Fluoroallene (MHz).  Calculation was made on the (1) PBE1PBE/6-31G(3d,3p) and (2) MP2/aug-cc-pVTZ structures.
   









Calc. (1)
Calc. (2)
Expt. [1]
   







Xaa - 38.08 - 38.06 - 37.74

Xbb
  1.68
  1.66
  1.18

Xcc
36.41
36.40
36.56

|Xab|
53.37
53.32



 







RMS
0.36 (1.4 %) 0.34 (1.4 %)


RSD
0.49 (1.1 %) 0.49 (1.1 %)


 







Xxx
38.75
38.70



Xyy
36.41
36.40



Xzz - 75.16 - 75.10



ETA - 0.031 - 0.031



Øa,z
34.78
34.79



Øa,CCl
35.70
35.70



Øz,CCl
  0.92
  0.91



 








 







 
 




Table 2. 1-Chloro-1-Fluoroallene.  Molecular structure parameters (Å and degrees).
 





r(1) = PBE1PBE/6-31G(3d,3p) optimization.

r(2) = MP2/aug-cc-pVTZ approximate re
 




Point Group: Cs

ropt (1)
ropt (2)







ClC(1)
1.7131
1.7111
FC(1)
1.3315
1.3334
C(1)C(2)
1.3007
1.3005
C(2)C(3)
1.3020
1.3055
C(3)H
1.0880
1.0832
ClC(1)F
112.42
112.43
ClC(1)C(2)
124.44
124.55
C(1)C(2)C(3)
178.89
178.82
C(2)C(3)H
121.46
121.05

HC(3)C(1)Cl
±89.80
±89.79



 








 



Table 3.  1-Chloro-1-Fluoroallene.  Rotational Constants (MHz).  35Cl Species.
 




r(1) = PBE1PBE/6-31G(3d,3p) optimization.

r(2) = MP2/aug-cc-pVTZ approximate re 
 




  Calc. r(1) Calc. r(2)    Expt. [1]






A    6801.8    6801.9 6781.35(20)

B    2837.3    2836.4 2825.740(8)

C    2030.0    2029.6 2019.404(10)


 








 








[1] T.Ogata, J.Mol.Spectrosc. 139,253(1990).


 








 








Chloroallene
 Bromoallene
 Cyanoallene


H2C=CFCl H2CFCl





 








 








Table of Contents




Molecules/Chlorine




 








 













ClFCCCH2.html






Last Modified 31 Dec 2011