CH3COCl



 









Chlorine


Nuclear Quadrupole Coupling Constants


in Acetyl Chloride


 







 
 
Chlorine nqcc's in acetyl chloride were determined by Hayashi et al. [1], which investigators also derived a substitution molecular structure.  Calculation of the nqcc's was made here on this structure and on a ~re structure given by MP2/aug-cc-pVTZ with empirically corrected C-C, C=O, and CCl bond lengths.  Calculated and experimental nqcc's are compared in Table 1, structure parameters in Table 2.
 
In Table 1, 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 for the B1LYP/TZV(3df,2p) model for calculation of the chlorine nqcc's. 
 
Subscripts a,b,c refer to the principal axes of the inertia tensor; x,y,z to the principal axes of the nqcc tensor.  The nqcc y-axis is chosen coincident with the inertia c-axis, these are perpendicular to the molecular symmetry plane.  Ø (degrees) is the angle between its subscripted parameters.  ETA = (Xxx - Xyy)/Xzz.

 







 
 
 






Table 1. Chlorine nqcc's in CH3COCl (MHz).  Calculation was made on the rs and ~re structures.
 








Calc / rs Calc / ~re
Expt. [1]
 





Xaa (35Cl) - 60.68 - 59.10 - 58.437(11)
Xbb 38.73 37.56 36.493(11)
Xcc 21.95 21.54 21.944(11)
|Xab|   8.80   9.70
 
RMS 1.83 (4.7 %) 0.76 (2.0 %)
RSD 0.49 (1.1 %) 0.49 (1.1 %)
 
Xxx 39.51 38.52
Xyy 21.95 21.54
Xzz - 61.46 - 60.07
ETA - 0.286 - 0.283
Øz,a 5.02 5.68
Øa,CCl 5.97 6.06
Øz,CCl 0.95 0.38
 
Xaa(37Cl) - 47.87 - 46.62 - 45.701(16)
Xbb 30.57 29.64 28.530(16)
Xcc 17.30 16.98 17.172(16)
|Xab|   6.70   7.46
 
RMS 1.72 (5.6 %) 0.84 (2.8 %)
RSD 0.44 (1.1 %) 0.44 (1.1 %)
 

 
 
Table 2.  Acetyl Chloride.  Molecular structure parameters, rs [1] and ~re (Å and degrees)
 
     r    ~re
CC 1.485(6) 1.4939
C=O 1.209(6) 1.1828
CCl 1.783(2) 1.7971
CH(1) 1.080(1) 1.0858
CH(3,4) 1.090(1) 1.0883
CCO 126.92(130) 128.08
CCCl 113.62(55) 111.42
CCH(1) 109.94(38) 109.39
CCH(3,4) 108.88(40) 109.06
H(1)CH(3,4) 110.85(15) 110.81
H(3)CH(4) 107.35(23) 107.67

 
 

[1] M.Hayashi, N.Inada, and Y.Niide, J.Mol.Struct. 352/353,325(1995).

 








 








O=CHCl O=CFCl O=CCl2
S=CCl2 S=CFCl s-t-CH2CHCOCl
 

 








Table of Contents




Molecules/Chlorine



 

 













CH3COCl.html






Last Modified 11 Aug 2009