CH3ClC=CH2						PDF
		Chlorine
	Nuclear Quadrupole Coupling Constants
		in 2-Chloropropene
	Calculation of the chlorine nqcc's in 2-chloropropene was made on a molecular structure derived ab initio, as described below.  Earlier measurements of the nqcc's were made by Good et al. [2] and Unland et al. [3].  The calculated nqcc's are compared with the experimental results of Fliege and Dreizler [1] in Table 1.  Structure parameters are given in Z-matrix format in Table 2.  Rotational constants are given in Table 3.
	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 2-Chloropropene (MHz).     Calc. Expt. [1]     35Cl Xaa - 68.36 - 68.072 Xbb 37.84 37.097 Xcc 30.51 30.975 |Xab|   9.73   RMS 0.53 (1.2 %) RSD 0.49 (1.1 %)   Xxx 38.73 37.99 * Xyy 30.51 30.975 Xzz - 69.24 - 68.96 ETA - 0.119 - 0.102 Øz,a 5.19 5.24 Øa,CCl 5.00 5.00 Øz,CCl 0.19 0.24     37Cl Xaa - 53.90 - 53.763 Xbb 29.86 29.370 Xcc 24.05 24.394 |Xab|   7.94   RMS 0.36 (0.99 %) RSD 0.44 (1.1 %)
	* Calculated here from the experimental diagonal nqcc's and the calculated off-diagonal nqcc.
	Molecular Structure
	The molecular structure was optimized at the MP2/6-311+G(d,p) level of theory assuming Cs symmetry.  The optimized CC bond lengths, single and double,  were corrected using equations obtained from linear regression analysis of the data given in Table IX of Ref.[4].  For the CCl bond, the structure was optimized at the MP2/6-311+G(2d,p) level and corrected by linear regression analysis of the data given in Table 4 of Ref.[5].  The CH bond lengths were corrected using r = 1.001 ropt, where ropt is obtained by MP2/6-31G(d,p) optimization [6].  Interatomic angles used in the calculation are those given by MP2/6-311+G(d,p) optimization.
	Table 2.  Z-Matrix (Å and degrees).   Cl C 1 R1 C 2 R2 1 A3 C 2 R3 1 A4 3 180. H 4 R4 2 A5 3 180. H 4 R5 2 A6 3     0. H 3 R6 2 A7 6     0. H 3 R7 2 A8 6 -D H 3 R7 2 A8 6 D   R1 = 1.740 A3 = 114.14 R2 = 1.491 A4 = 120.15 R3 = 1.330 A5 = 121.87 R4 = 1.080 A6 = 119.34 R5 = 1.081 A7 = 110.08 R6 = 1.089 A8 = 110.38 R7 = 1.090 D = 120.49
	Table 3.  Rotational Constants (MHz).  35Cl species.   Calc. ropt      Expt. [1] A 9 380.8 9 271.706(79) B 4 985.9 4 983.816(45) C 3 322.4 3 304.414(45)
	[1] E.Fliege and H.Dreizler, Z.Naturforsch. 38a,1231(1983).
	[2] W.Good, R.J.Conan Jr., A.Bauder, and Hs.H.Günthard, J.Mol.Spectrosc. 41,381(1972).
	[3] M.L.Unland, V.Weiss, and W.H.Flygare, J.Chem.Phys. 42,2138(1965).
	[4] J.Demaison, J.Cosléou, R.Bocquet, and A.G.Lesarri, J.Mol.Spectrosc. 167,400(1994).
	[5] I.Merke, L.Poteau, G.Wlodarczak, A.Bouddou, and J.Demaison, J.Mol.Spectrosc. 177,232(1996).
	[6] J.Demaison and G.Wlodarczak, Structural Chem. 5,57(1994).
	H2C=CHCl			H2C=CFCl			c-ClHC=CHCl
	c-FHC=CHCl			t-FHC=CHCl			H2C=CCl2
	H2C=CClCN			F2C=CHCl			F2C=CCl2
	(CH3)2C=CHCl			Cl2C=CHCl			F2C=CFCl
	c-CH3HC=CHCl			t-CH3HC=CHCl			CH2ClHC=CH2
	c-CH3FC=CHCl
	Table of Contents
	Molecules/Chlorine
						2ClPropene.html
						Last Modified 21 June 2004