CHFCl2




 






















 








 









Chlorine


Nuclear Quadrupole Coupling Constants

in Dichlorofluoromethane


 








 








 








Chlorine nqcc's in dichlorofluoromethane have been determined by Alonso et al. [1,2], who also derived an "ro-like" structure [1], in which the CH bond length and FCH angle are assumed parameters.  Calculation was made here of the chlorine nqcc's on this molecular structure, and on an ropt structure given by CCSD(T)_AE/wCVQZ optimization [3].  Calculated and experimental nqcc's are compared in Tables 1 - 3.  Structure parameters are given in Table 4, atomic coordinates in Table 5.

 








In Tables 1 - 3, subscripts a,b,c refer to the principal axes of the inertia tensor; x,y,z to the principal axes of the nqcc tensor.  z,CCl (degrees) is the angle between the principal z-axis of the nqcc tensor and the CCl bond axis.  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 chlorine efg's/nqcc's.

 









 







 
   








Table 1.  35Cl nqcc's in CHF35Cl2 (MHz).  Calculation was made (1) on the ro-like structure [1], and (2) on the ropt = CCSD(T)_AE/wCVQZ optimization structure [3].

   










Calc. (1)

Calc. (2)
Expt. [2]
   








Xaa - 40.97 - 41.35 - 40.8921(19)

Xbb
10.85
11.42
11.4127(30)

Xcc
30.11
29.92
29.4794(30)

Xab 45.57 45.05 44.63(43)

Xac 25.73 26.05 26.18(96)

Xbc - 13.83 - 13.74 - 13.63(51)

 







RMS
0.49 (1.8 %) 0.37 (1.3 %)


RSD
0.49 (1.1 %) 0.49 (1.1 %)


 







Xxx
36.74
36.61
36.19(92)

Xyy
38.80
38.79
38.6(12)

Xzz - 75.54 - 75.40 - 74.81(91)

ETA
0.027
0.029



z,CCl
1.09
1.15



 








 








 








   








Table 2.  Chlorine nqcc's in CHF35Cl37Cl (MHz).  Calculation was made (1) on the ro-like structure [1], and (2) on the ropt = CCSD(T)_AE/wCVQZ optimization structure [3].
   








35Cl
Calc. (1)

Calc. (2)
Expt. [2]
   








Xaa - 39.36 - 39.75 - 39.3009(67)

Xbb
  9.27
  9.86
  9.849(15)

Xcc
30.08
29.89
29.452(15)

Xab - 46.43 - 45.93



Xac - 25.52 - 25.85



Xbc - 14.29 - 14.21



 







RMS
0.49 (1.9 %) 0.36 (1.4 %)


RSD
0.49 (1.1 %) 0.49 (1.1 %)


 







37Cl
Calc. (1)
Calc. (2)
Expt. [2]

 







Xaa - 33.56 - 33.82 - 33.4548(78)

Xbb
  9.77
10.18
10.165(15)

Xcc
23.79
23.64
23.290(15)

Xab
35.97
34.81



Xac
18.99
20.62



Xbc - 10.53 - 10.43



 







RMS
0.37 (1.7 %) 0.29 (1.3 %)


RSD
0.44 (1.1 %) 0.44 (1.1 %)


 








 








 








   








Table 3.  37Cl nqcc's in CHF37Cl2 (MHz).  Calculation was made (1) on the ro-like structure [1], and (2) on the ropt = CCSD(T)_AE/wCVQZ optimization structure [3].
   










Calc. (1)

Calc. (2)
Expt. [2]
   








Xaa - 32.29 - 32.59 - 32.2262(20)

Xbb
  8.52
  8.97
  8.9588(33)

Xcc
23.77
23.62
23.2674(33)

Xab 35.95 35.55 35.36(41)

Xac 20.22 20.47 19.3(12)

Xbc - 10.87 - 10.81 - 10.51(70)

 







RMS
0.39 (1.8 %) 0.29 (1.4 %)


RSD
0.44 (1.1 %) 0.44 (1.1 %)


 








 








 








 


Table 4.  Dichlorofluoromethane.  Structure parameters ( and degrees).   
 




ro-like [1]
ropt [3]





CCl 1.764(2) 1.7571

CF 1.335(5) 1.3436

CH 1.09 (ass.)
1.0826

HCF 110.0 (ass.)
109.587

FCCl 109.6(2) 109.342

ClCCl 111.0(2) 111.416



 








 







Table 5.   CHF35Cl2.  Atomic coordinates, ro-like (top row) and ropt (bottom row) structures.
 











  a ()
  b ()
  c ()











Cl 1.4538 - 0.5019 - 0.0533



1.4517 - 0.5000 - 0.0539


F
0.0
1.5840 - 0.1497




0.0
1.5833 - 0.1485


C
0.0
0.3773
0.4213




0.0
0.3674
0.4232


H
0.0
0.4784
1.5066




0.0
0.4730
1.5001


 








 








[1] A.deLuis, J.C.Lpez, A.Guarnieri, and J.L.Alonso, J.Mol.Struct. 413-414,249(1997).

[2] J.C.Lpez, A.deLuis, S.Blanco, A.Lessari, and J.L.Alonso, J.Mol.Struct. 612,287(2002).

[3] N.Vogt, J.Demaison, and H.D.Rudolph, Mol.Phys. 112,2873(2014).

 








D.B.McLay, Can.J.Phys. 42,720(1964):  For CHF35Cl2 species; Xaa = -41.0(2) MHz, Xbb = 11.37(13) MHz, and Xcc = 29.62(13) MHz.


 









 








CH3Cl CH2Cl2 CHCl3 CH2FCl

CF3Cl CF2Cl2 CFCl3 CHF2Cl

Calculation of Cl Nuclear Quadrupole Coupling Constants on Approximate Equilibrium Structures of Cl,F-Methanes: Gaussian.

Calculation of Cl Nuclear Quadrupole Coupling Constants on Approximate Equilibrium Structures of Cl,F-Methanes: GAMESS.

 








 








Table of Contents




Molecules/Chlorine




 








 













CHFCl2.html






Last Modified 5 July 2014