CH2ClCH2CN
	Chlorine and Nitrogen
	Nuclear Quadrupole Coupling Constants
	in trans 3-Chloropropionitrile
	Calculation of the chlorine and nitrogen nqcc tensors in the trans (Cs) conformer of 3-chloropropionitrile was made on a structure derived ab initio as discussed below.   These are given in Tables 1 - 4.  Only Xaa for both 35Cl and 37Cl have been determined experimentally [1].  These are given in Tables 1 and 2.  Structure parameters are shown in Table 5, rotational constants in Table 6.
	The trans confomer is lower in energy than the gauche conformer by about 1 kcal/mole as calculated at the B1LYP/TZV(3df,2p) and B3PW91/6-311+G(df,pd) levels of theory.
	In Tables 1 - 4, 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.
	RMS is the root mean square difference between calculated and experimental nqcc's (percentage of the average experimental nqcc).  RSD is the residual standard deviation of calibration of the model for calculation of the nqcc's.
	Table 1.  35Cl nqcc's in trans CH2ClCH2CN (MHz).     Calc. Expt. [1]     35Cl Xaa - 61.35 - 58.8(9) Xbb 23.81 Xcc 37.53 |Xab| 34.67   RSD 0.49 (1.1 %)   Xxx 36.14 Xyy 37.53 Xzz - 73.68 ETA 0.019 Øz,a 19.58 Øa,CCl 19.06 Øz,CCl   0.52
	Table 2.  37Cl nqcc's in trans CH2ClCH2CN (MHz).     Calc. Expt. [1]     37Cl Xaa - 48.36 - 47.6(8) Xbb 18.78 Xcc 29.58 |Xab| 27.31   RSD 0.44 (1.1 %)   Xxx 28.48 Xyy 29.58 Xzz - 58.06 ETA 0.019 Øz,a 19.56
	Table 3.  14N nqcc's in trans CH235ClCH2CN (MHz).     Calc. Expt.     14N Xaa - 3.532 Xbb 1.507 Xcc 2.025 |Xab| 2.115   RSD 0.030 (1.3 %)   Xxx 2.277 Xyy 2.025 Xzz - 4.302 ETA - 0.058 Øz,a 20.00 Øa,CN 20.34 Øz,CN   0.34
	Table 4.  14N nqcc's in trans CH237ClCH2CN (MHz).     Calc. Expt.     14N Xaa - 3.533 Xbb 1.508 Xcc 2.025 |Xab| 2.114   RSD 0.030 (1.3 %)
	Molecular Structure
	The molecular structure was optimized at the MP2/6-311+G(d,p) level of theory.  The optimized C-C, C-C(N), and CN bond lengths were corrected using equations obtained from linear regression analyses of the data given in Tables VIII and IX of Ref. [2].   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. [3].  The CH bond lengths were corrected using r = 1.001 ropt, where ropt is obtained by MP2/6-31G(d,p) optimization [4].  Interatomic angles used in the calculation are those given by MP2/6-311+G(2d,p) optimization.
	Table 5.  trans 3-Chloropropionitrile.  Heavy atom structure parameters (Å and degrees).  The complete structure is given here in Z-Matrix format.   NC(8) 1.1561 C(8)C(3) 1.4609 C(3)C(2) 1.5204 C(2)Cl 1.7757 NC(8)C(3) 178.45 C(8)C(3)C(2) 110.10 C(3)C(2)Cl 109.83
	Table 6.  trans 3-Chloropropionitrile.  Rotational constants (MHz).  Normal species.   Calc. ropt    Expt. [1] A 27 115.4 26 818.74(35.13) B   1 518.2   1 508.89(1) C   1 464.0   1 454.62(1)
	[1] S.Xu and M.D.Harmony, J.Mol.Struct. 274,115(1992).
	[2] J.Demaison, J.Cosléou, R.Bocquet, and A.G.Lesarri, J.Mol.Spectrosc. 167,400(1994).
	[3] I.Merke, L.Poteau, G.Wlodarczak, A.Bouddou, and J.Demaison, J.Mol.Spectrosc. 177,232(1996).
	[4] J.Demaison and G.Wlodarczak, Structural Chem. 5,57(1994).
	g-3-Chloropropionitrile			2-Chloropropionitrile
	Ethyl Cyanide			Chloroacetonitrile
	Ethyl Chloride			t-3-Bromopropionitrile
	Table of Contents
	Molecules/Chlorine
	Molecules/Nitrogen
						tCH2ClCH2CN.html
						Last Modified 9 July 2006