ClHC=C=CH2
























 








 









Chlorine


Nuclear Quadrupole Coupling Constants

in Chloroallene


 








 








 


 





Chlorine nuclear quadrupole coupling constants in chloroallene were first determined by Moon et al. [1], subsequently revisited by Ogata and Niide [2].


 








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 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; subscripts x,y,z to the principal axes of the nqcc tensor.  (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,3p) model for calculation of the nqcc's.

 








 








   








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










Calc. (1)

Calc. (2)
Expt. [2]
   








Xaa -
42.88
-
41.84
-
41.63(14)


Xbb
  8.49

  7.31

  6.73


Xcc
34.39

34.53

34.90


|Xab|
51.90

52.44




 







RMS
1.28 (5.9 %)
0.42 (1.5 %)



RSD
0.49 (1.1 %)
0.49 (1.1 %)


 







Xxx
40.72

40.65




Xyy
34.39

34.53




Xzz -
75.10
-
75.18




ETA -
0.08428
-
0.08141




a,z
31.84

32.45




a,CCl
32.61

33.03




z,CCl
  0.77

  0.58




 








 








 









   








Table 2.  37Cl nqcc's in Chloroallene (MHz).  Calculation was made on the (1) PBE1PBE/6-31G(3d,3p) and (2) MP2/aug-cc-pVTZ structures.
   










Calc. (1)

Calc. (2)
Expt. [2]
   








Xaa -
34.08
-
33.27
-
32.62(19)


Xbb
  6.98

  6.06

  5.31


Xcc
27.10

27.21

27.31


|Xab|
40.76

41.19

41.10(81)


 







RMS
1.29 (5.9 %)
0.57 (2.6 %)



RSD
0.44 (1.1 %)
0.44 (1.1 %)


 








 









 








 
 




Table 3. Chloroallene.  Molecular structure parameters ( 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(2)
1.7329

1.7340
HC(2)
1.0833

1.0793
C(2)C(4)
1.3017

1.3026
C(4)C(5)
1.3021

1.3054
C(5)H
1.0871

1.0824
ClC(2)H
113.76

114.38
ClC(2)C(4)
122.94

122.25
C(2)C(4)C(5)
179.38

179.42
C(4)C(5)H
121.27

120.85
HC(5)C(2)Cl
90.23

90.14



 








 



Table 4.  Chloroallene.  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. [2]






A 33087.3
32508.6
32403.126(22)

B   2844.9
  2858.8
  2850.4714(23)

C   2667.8
  2676.2
  2665.0806(16)


 








 








[1] H.Moon, J.H.Goldstein, and J.W.Simmons, Spectrochim. Acta 16,1267(1960):  Abstract only.


[2] T.Ogata and Y.Niide, J.Chem.Soc. Faraday Trans. 92,4889(1996).


 








 








Bromoallene
ClFC=C=CH2
Cyanoallene
H2C=CHCl

 








 








Table of Contents




Molecules/Chlorine




 








 













ClHCCCH2.html






Last Modified 31 Dec 2011