CH2=C=C=CHCl
		Chlorine
	Nuclear Quadrupole Coupling Constants
		in Chlorobutatriene
	Calculation of the chlorine nqcc's in chlorobutatriene was made on an approximate equilibrium structure derived here by MP2/aug-cc-pVTZ optimization with empirically corrected bond lengths.  These nqcc's are compared with the available experimental values [1] in Table 1.  Structure parameters are given in Table 2, rotational constants in Table 3.
	In Table 1, 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.
	RSD is the calibration residual standard deviation for the B1LYP/TZV(3df,2p) model for calculation of the chlorine nqcc's, which may be taken as an estimate of the uncertainty in the calculated coupling constants.
	Table 1. Chlorine nqcc's in CH2=C=C=CHCl (MHz).     Calc. Expt. [1]     35Cl Xaa - 26.14 - 25.8(5) Xbb - 4.34 Xcc 30.48 |Xab| 56.22   RSD 0.49 (1.1 %)   Xxx 42.02 Xyy 30.48 Xzz - 72.50 ETA - 0.159 Øz,a 39.51 Øa,CCl 39.94 Øz,CCl   0.43     37Cl Xaa - 20.94 Xbb - 3.09 Xcc 24.02 |Xab| 44.24   RSD 0.44 (1.1 %)
	Table 2.  CH2=C=C=CHCl  Heavy atom structure parameters (Å and degrees).  Complete structure is given here in Z-matix format.   Parameter  reapprox C(1)=C(4) 1.3171 C(4)=C(5) 1.2662 C(5)=C(6) 1.3135 C(6)-Cl 1.7272 C(5)=C(6)Cl 122.46
	Table 3.  CH2=C=C=CH35Cl Rotational Constants (MHz).  Calc is on the reapprox molecular structure.     Calc.   Expt. [1] A 25095.5 25181(50) B   1555.6   1551.10(2) C   1464.8   1459.80(2)
	[1] F.Karlsson, M.Granberg, and R.Vestin, Acta Chem. Scand. A28(2),6(1974).
	t-1-Chlorobuten-3-yne		2-Chlorobuten-3-yne		4-Chlorobuten-3-yne
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	Molecules/Chlorine
						CH2CCCHCl.html
						Last Modified 29 Nov 2011