CH2F-CF2Cl
		Chlorine
	Nuclear Quadrupole Coupling Constants
	in 1-Chloro-1,1,2-Trifluoroethane
	Calculations of the chlorine nqcc tensors in trans and gauche conformers of 1-chloro-1,1,2-trifluoroethane shown below were made on molecular structures given by MP2/aug-cc-pVTZ optimization (ropt), and on same but with ~re CCl, C-C, and CF bond lengths.  (Also, see Calculation of Nuclear Quadrupole Coupling Constants on Approximate Equilibrium Structures: Ethanes.)  Relative energies shown below are energies calculated at the B1LYP/TZV(3df,2p) level of theory.
		trans  E = 0				gauche  E = 1.9 kJ/mole
	Calculated nqcc tensors are given in Tables 1 - 4.  Structure parameters are given in Table 5.  Rotational constants and dipole moments (given by B1LYP/TZV(3df,2p) calculation) are given in Tables 6 and 7.
	In Tables 1 - 4, subscripts a,b,c refer to the principal axes of the inertia tensor; 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 chlorine nqcc's.
	Table 1.  35Cl nqcc's in trans conformer of CH2F-CF2Cl (MHz).       ropt ~re Expt. [1]     Xaa - 58.19 - 57.84 - 57.958(10) Xbb 21.15 21.02 21.231(11) Xcc 37.04 36.82 36.727(11) |Xab| 36.79 36.54   RMS 0.23 (0.6 %) 0.15 (0.4 %) RSD 0.49 (1.1 %) 0.49 (1.1 %)   Xxx 35.59 35.35 Xyy 37.04 36.82 Xzz - 72.62 - 72.17 ETA 0.020 0.020 Øz,a 21.42 21.41 Øa,CCl 22.03 22.08 Øz,CCl   0.61   0.67
	Table 2.  37Cl nqcc's in trans conformer of CH2F-CF2Cl (MHz).         ropt   ~re Expt. [1]     Xaa - 46.46 - 46.19 - 46.268(11) Xbb 17.28 17.17 17.319(13) Xcc 29.19 29.02 28.949(13) |Xab| 28.33 28.14   RMS 0.18 (0.6 %) 0.11 (0.3 %) RSD 0.44 (1.1 %) 0.44 (1.1 %)
	Table 3.  35Cl nqcc's in gauche conformer of CH2F-CF2Cl (MHz).         ropt   ~re Expt.     Xaa   9.00   8.31 Xbb - 46.02 - 45.13 Xcc 37.02 36.82 Xab 48.77 48.80 Xac   0.92   0.89 Xbc - 1.09 - 1.08   RSD 0.49 (1.1 %) 0.49 (1.1 %)   Xxx 36.92 36.74 Xyy 37.59 37.32 Xzz - 74.52 - 74.06 ETA 0.009 0.008 Øz,CCl   0.81   0.89
	Table 4.  37Cl nqcc's in gauche conformer of CH2F-CF2Cl (MHz).         ropt   ~re Expt.     Xaa   2.99   2.46 Xbb - 32.17 - 31.48 Xcc 29.18 29.02 Xab 40.48 40.43 Xac   0.71   0.69 Xbc - 0.73 - 0.73   RSD 0.44 (1.1 %) 0.44 (1.1 %)
	Table 3.  CH2F-CF2Cl.  Selected structure parameters (Å and degrees).  Complete structures are given here in Z-matrix format.   CS trans   ropt    ~re   C(2)Cl 1.7699 1.7666 C(2)F(4,5) 1.3422 1.3360 C(2)C(3) 1.5144 1.5126 C(3)F 1.3756 1.3688 C(3)C(2)Cl 108.78 108.78 C(3)C(2)F(4,5) 111.08 111.08 FC(2)F 107.47 107.47 FC(2)Cl 109.21 109.21     C1 gauche   ropt    ~re C(2)Cl 1.7607 1.7574 C(2)F(4) 1.3495 1.3433 C(2)F(5) 1.3434 1.3372 C(3)C(2)Cl 112.33 112.33 C(3)C(2)F(4) 107.79 107.79 C(3)C(2)F(5) 110.75 110.75 FC(2)F 107.62 107.62 F(4)C(2)Cl 109.27 109.27 F(5)C(2)Cl 108.95 108.95
	Table 4.  trans CH2F-CF235Cl.  Rotational Constants (MHz) and Dipole Moments (D).   ropt    ~re Expt. [1] A 4612.39 4643.31 4625.161(3) B 2007.41 2018.92 2004.127(2) C 1878.09 1887.57 1875.813(2)   |mua| 0.53 |mub| 1.96 |muc| 0.00 mutot 2.08 2.03
	Table 5.  gauche CH2F-CF235Cl.  Equilibrium Rotational Constants (MHz) and Dipole Moments (D).   ropt    ~re Expt. A 3349.62 3371.75 B 2598.11 2612.37 C 2021.56 2032.03   |mua| 0.64 0.65 |mub| 0.64 0.64 |muc| 1.51 1.48 mutot 1.76 1.74
	[1] B.Liu, Y.Tatamitani, J.Shimada, and T.Ogata, J.Mol.Spectrosc. 211,99(2002).
	CHF2-CHFCl		CHF2-CH2Cl		CHF2-CF2Cl		CF3-CF2Cl
	Calculation of Nuclear Quadrupole Coupling Constants on Approximate Equilibrium Structures: Ethanes
	Table of Contents
	Molecules/Chlorine
						CH2FCF2Cl.html
						Last Modified 18 Dec 2009