CCl2
		Chlorine
	Nuclear Quadrupole Coupling Constants
		in Dichloromethylene
	Calculation of the Cl nqcc tensors in CCl2 was made on ro [1] and re [3] structures.  These calculated nqcc's are compared with the experimental values [1,2] in Tables 1 - 3.  Structure parameters are given in Table 4.
	In Tables 1 - 3, 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 computational model residual standard deviation. 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.
	Table 1.  35Cl nqcc's in C35Cl2 (MHz).  Calculation was made on ro [1] and re [3] structures.   Calc / re Calc / ro Expt. [1,2]   Xaa - 22.70 - 23.02 - 22.859 Xbb 18.46 18.66 17.319(1) Xcc   4.24   4.36   5.540(1) |Xab| 46.55 46.46 46.2(2)     RMS 1.00 (6.6 %) 1.04 (6.8 %) RSD 0.49 (1.1 %) 0.49 (1.1 %)     Xxx 48.78 48.74 47.6(1) Xyy   4.24   4.36   5.540(1) Xzz - 53.02 - 53.10 - 53.1(1) ETA - 0.840 - 0.836 Øz,b* 56.93 57.08 Øb,CCl 54.61 54.674 Øz,CCl   2.32   2.41
	*The b-axis coincides with the bisector of the ClCCl angle.
	Table 2.  Chlorine nqcc's in C35Cl37Cl (MHz).  Calculation was made on ro [1] and re [3] structures.   Calc / re Calc / ro Expt. [1]   Xaa(35Cl) - 22.42 - 22.74 - 22.594 Xbb 18.18 18.38 17.055(14) Xcc   4.24   4.36   5.539(23) |Xab| 46.67 46.59 47.7(11)     RMS 1.00 (6.6 %) 1.03 (6.8 %) RSD 0.49 (1.1 %) 0.49 (1.1 %)     Xaa(37Cl) - 18.11 - 18.36 - 18.238 Xbb 14.77 14.93 13.845(17) Xcc   3.34   3.43   4.393(28) |Xab| 36.59 36.52 37.6(9)   RMS 0.81 (6.7 %) 0.84 (6.9 %) RSD 0.44 (1.1 %) 0.44 (1.1 %)
	Table 3.  37Cl nqcc's in C37Cl2 (MHz).  Calculation was made on ro [1] and re [3] structures.   Calc / re Calc / ro Expt. [1]   Xaa - 17.89 - 18.14 - 18.014 Xbb 14.55 14.71 13.653(1) Xcc   3.34   3.43   4.361(3) |Xab| 36.69 36.62 37.2(3)     RMS 0.79 (6.6 %) 0.82 (6.8 %) RSD 0.44 (1.1 %) 0.44 (1.1 %)     Xxx 38.44 38.42 38.2(1) Xyy   3.34   3.43   4.361(3) Xzz - 41.78 - 41.58 - 42.6(1) ETA - 0.840 - 0.842 Øz,b* 56.93 57.08 Øb,CCl 54.61 54.674 Øz,CCl   2.32   2.41
	*The b-axis coincides with the bisector of the ClCCl angle.
	Table 4.  CCl2  Molecular Structure Parameters (Å and degrees).   ro [1] re [3] CCl 1.7141 1.7113 ClCCl 109.349 109.22
	[1] T.Pancur, K.Brendel, N.Hansen, H.Mäder, V.Markov, and F.Temps, J.Mol.Spectrosc. 232,375(2005).
	[2] N.Hansen, H.Mäder, and F.Temps, Phys.Chem.Chem.Phys., 3,50 (2001).
	[3] J.Demaison, L.Margulès, J.M.L.Martin, and J.E.Boggs, Phys.Chem.Chem.Phys. 4,3282(2002).
	M.Fujitake and E.Hirota, J.Chem.Phys. 91,3426(1989):  ro structure, CCl = 1.7157(28) Å and ClCCl = 109.2(3)o;  Cl nqcc's, Xaa, Xbb, Xcc  =  -22.61(132), 17.40(85), 5.21(85) MHz.
	CH2Cl2		CF2Cl2		O=CCl2		H2C=CCl2
	S=CCl2
	Table of Contents
	Molecules/Chlorine
						CCl2.html
						Last Modified 3 Feb 2009