C5H7Cl
		Chlorine
	Nuclear Quadrupole Coupling Constants
	in 1-Chlorocyclopentene
	Calculation of the chlorine nqcc tensors in 1-chlorocyclopentene was made on the molecular structures given by MP2/6-311+G(2d,p) optimization assuming Cs and C1 symmetry (see figure below).  For each, empirical correction was made of the C-H and C-Cl bond lengths.   These calculated nqcc's are compared with the experimental nqcc's of Caminati et al. [1] in Table 1.  Structure parameters are given here in z-matrix format (Gaussian 03 input).  Rotational constants are given in Table 3.
		Cs					C1
	Note:  E(C1) < E(Cs) by 0.7 kcal/mol, where the energies are those of the MP2/6-311+G(2d,p) optimized structures.
	In Tables 1 and 2, 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.  RSD is the calibration residual standard deviation of the B1LYP/TZV(3df,3p) model for calculation of the chlorine nqcc's, which may be taken as an estimate of the uncertainty in the calculated nqcc's.
	Table 1.  35Cl nqcc's in 1-Chlorocyclopentene (MHz).     Calc / C1 Calc / Cs Expt. [1]     Xaa - 69.53 - 69.49 - 69.1 Xbb 38.49 38.32 38.0 Xcc 31.04 31.18 31.1 |Xab|   3.22 *   3.12 |Xac|   1.56   0 ** |Xbc|   0.13   0 **   RMS 0.4 (0.82 %) 0.3 (0.64 %) RSD 0.49 (1.1 %) 0.49 (1.1 %)   Xxx 38.59 38.41 Xyy 31.07 31.18 Xzz - 69.66 - 69.58 ETA - 0.108 - 0.104 Øz,a 1.92 1.65 Øa,CCl 1.82 1.50 Øz,CCl 0.16 0.15
	* The product XabXacXbc is negative.    ** By symmetry.
	Table 2.  37Cl nqcc's in 1-Chlorocyclopentene (MHz).     Calc / C1 Calc / Cs Expt.     Xaa - 54.80 - 54.77 Xbb 30.33 30.20 Xcc 24.47 24.57 |Xab|   2.54 *   2.47 |Xac|   1.20   0 ** |Xbc|   0.10   0 **   RSD 0.49 (1.1 %) 0.49 (1.1 %)
	* The product XabXacXbc is negative.    ** By symmetry.
	Table 3.  1-Chlorocyclopentene.  Rotational Constants (MHz).  35Cl species.   Calc C1 Calc Cs Expt. [1] A 7220.1 7176.6 7173.51(15) B 1899.0 1891.0 1889.524(3) C 1557.6 1539.1 1547.004(4) Note:  The substitution |a| coordinate of Cl is 1.9589(5) Å; |b| and |c| are small [1].  The C1 and Cs (|a|, |b|, |c|) are respectively (1.9552, 0.0048, 0.0219 Å) and (1.9588, 0.0062, 0 Å).
	[1] W.Caminati, R.Danieli, A.C.Fantoni, and J.C.Lopez, J.Mol.Spectrosc. 181,91(1997).
	1,1-Dichlorocyclopropane			Cyclobutyl Chloride
	Cyclopropyl Chloride			Cyclohexyl Chloride
	(Chloromethyl)cyclopropane			(Chloromethyl)oxirane
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	Molecules/Chlorine
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						Last Modified 18 Dec 2008