H2C=P-CN
	Nitrogen
	Nuclear Quadrupole Coupling Constants
		in P-Cyanophosphaethene
	Calculation of the nitrogen nqcc tensor in P-cyanophosphaethene was made here on molecular structures given by MP2/6-311+G(3df,3pd) and MP2/aug-cc-pVTZ optimization, each corrected with approximate equilibrium CN bond length.  These nqcc's are given in Table 1.  Structure parameters are given in Z-matrix format in Table 2,  rotational constants in Table 3, dipole moments and quartic centrifugal distortion constants in Table 4.
	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.  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 H2C=P-CN (MHz).  Calculation was made here on molecular structures given by (1) MP2/6-311+G(3df,3pd) and (2) MP2/aug-cc-pVTZ optimization, each with approximate re(CN).   Calc (1) Calc (2) Expt   Xaa - 4.274 - 4.248 Xbb 1.743 1.734 Xcc 2.531 2.514 Xab 1.690 1.709 RSD 0.030 (1.3 %) 0.030 (1.3 %) Xxx 2.185 2.188 Xyy 2.531 2.514 Xzz - 4.716 - 4.702 ETA 0.073 0.069 Øz,a 16.66 14.87 Øa,CN 13.22 13.48 Øz,CN   1.44   1.39
	Table 2.  H2C=P-CN.  Optimized structure parameters (Å and degrees).  Approximate re(CN) bond lengths are given in parentheses.  P  C,1,B1  H,2,B2,1,A1  H,2,B3,1,A2,3,D1,0  C,1,B4,2,A3,3,D2,0  N,5,B5,1,A4,2,D3,0 MP2/6-311+G(3df,3pd) MP2/aug-cc-pVTZ  B1=1.66504944  B2=1.08109894  B3=1.08316835  B4=1.78184159  B5=1.17575297   (1.1604)  A1=124.88341033  A2=117.51712255  A3=99.34623492  A4=174.61875209  D1=180.  D2=0.  D3=180.  B1=1.67204007  B2=1.08141145  B3=1.08357648  B4=1.78860298  B5=1.17733864   (1.1606)  A1=124.80092327  A2=117.55695198  A3=98.95303402  A4=174.97920767  D1=180.  D2=0.  D3=180.
	Table 3.  H2C=P-CN.  Rotational Constants (MHz).  Calc (1) = MP2/6-311+G(3df,3pd) and Calc (2) =  MP2/aug-cc-pVTZ optimization, each with approximate re(CN). Calc (1) Calc (2)   Expt [1] A 20155 19849 20127.0(16) B   4088   4083   4067.758(11) C   3399   3386   3377.722(11)
	Table 4.  H2C=P-CN.  Dipole Moments and Quartic Centrifugal Distortion Constants.  Calc (1) = B3LYP/cc-pVTZ and Calc (2) = MP2/cc-pVTZ. Calc (1) Calc (2) Expt [1] |µa| /D 3.64 3.44 |µb| /D 0.30 0.25   Delta_J /kHz 1.58 1.64 1.53(21) Delta_JK /kHz - 0.456 + 0.579 - 1.14(33) Delta_K /kHz 241. 213. delta_J /kHz 0.439 0.469 delta_K /kHz 15.8 16.4 DJ /kHz 1.42 1.47 DJK /kHz 0.478 1.62 DK /kHz 240. 212. d1 /kHz - 0.439 - 0.469 d2 /kHz - 0.0778 - 0.0872
	[1] M.C.Durrant, H.W.Kroto, and D.R.M.Walton, J.Mol.Spectrosc. 121,304(1987).
	H2C=N-CN		H2C=P-Cl		H2P-CN
	Table of Contents
	Molecules/Nitrogen
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						Last Modified 4 Feb 2014