CH3-O-CH2CH2CN
	Nitrogen
	Nuclear Quadrupole Coupling Constants
		in 3-Methoxypropionitrile
	The microwave spectrum of 3-methoxypropionitrile has been investigated by Lowe and Kewley [1].  The spectrum revealed the presence of only one rotational isomer, the fully trans form with Cs symmetry.
	Calculation of the nitrogen nqcc tensor was made here on a molecular structure given by MP2/6-311+G(3df,3pd) optimization (trans assumed) with approximate equilibrium C-C and CN triple bond lengths.  These calculated nqcc's are given in Table 1, structure parameters in Table 2, rotational constants  in Table 3.
	In Table 1, 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.  The nqcc y-axis is chosen coincident with the inertia c-axis, these are perpendicular to the Cs plane of the molecule.  ETA = (Xxx - Xyy)/Xzz.  Ø (degrees) is the angle between its subscripted parameters.
	RSD is the residual standard deviation of calibration of the B3PW91/6-311+G(df,pd) model for calculation of the efg's/nqcc's.
	Table 1. Nitrogen nqcc's in 3-Methoxypropionitrile (MHz).     Calc. Expt.     14N Xaa - 2.815 Xbb 0.789 Xcc 2.026 Xab 2.684   RSD 0.030 (1.3 %)   Xxx 2.220 Xyy 2.026 Xzz - 4.246 ETA 0.0457 Øz,a 28.06 Øa,CN 28.56 Øz,CN   0.50
	Table 2.  3-Methoxypropionitrile.  Molecular structure parameters (Å and degrees).       MP2/6-311+G(3df,3pd) opt structure with approximate equilibrium bond lengths given in parentheses.    C  O,1,B1  H,1,B2,2,A1  H,1,B3,2,A2,3,D1,0  H,1,B4,2,A3,3,D2,0  C,2,B5,1,A4,3,D3,0  C,6,B6,2,A5,1,D4,0  H,6,B7,2,A6,1,D5,0  H,6,B8,2,A7,1,D6,0  H,7,B9,6,A8,2,D7,0  H,7,B10,6,A9,2,D8,0  C,7,B11,6,A10,2,D9,0  N,12,B12,6,A11,2,D10,0    B1=1.41281591  B2=1.08518555  B3=1.09327873  B4=1.09327873  B5=1.40489585  B6=1.52243881      (1.5203)  B7=1.09576103  B8=1.09576103  B9=1.0889796  B10=1.0889796  B11=1.45808134     (1.4590)  B12=1.16922872     (1.1560)  A1=107.18235654  A2=111.0041039  A3=111.0041039  A4=111.48042528  A5=106.75328087  A6=110.86954725  A7=110.86954725  A8=109.46721318  A9=109.46721318  A10=110.93028762  A11=142.80569612  D1=119.38969309  D2=-119.38969309  D3=180.  D4=180.  D5=-60.02817226  D6=60.02817226  D7=-59.10041226  D8=59.10041226  D9=180.  D10=180.
	Table 3.  3-Methoxypropionitrile  Rotational Constants (MHz).  Calc   Expt. [1]  A 17730 17821(14)  B   1439   1425.526(5)  C   1365   1353.909(10)
	[1] R.S.Lowe and R.Kewley, J.Mol.Spectrosc. 63,216(1976).
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	Molecules/Nitrogen
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						Last Modified 27 Dec 2013