CH3-CHI-CH2-CH3
	Iodine
	Nuclear Quadrupole Coupling Constants
		in 2-Iodobutane A
	G			A			G'
	Click on G, G' to view results for these conformers.
	Calculation of the iodine nqcc tensor in the A conformer of 2-iodobutane was made on molecular structures obtained by MP2/6-311+G(d,p) and MP2/6-311+G(3df,3pd) optimization.  These calculated nqcc's are compared with the experimental values of Arsenault et al. [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, subscripts x,y,z to the principal axes of the nqcc tensor.  Øz,CI (degrees) is the angle the z-principal axis makes with the CI bond axis.  ETA = (Xxx - Xyy)/Xzz.
	RMS is the root mean square difference between calculated and experimental diagonal nqcc's (percent of the average of the magnitudes of the experimental nqcc's).  RSD is the residual standard deviation of calibration of the B1LYP/6-311G(df,p) model for calculation of the efg's/nqcc's.
	Table 1.  127I nqcc's in A-2-Iodobutane (MHz).  Calculation was made on the following structures:  ropt (1) = MP2/6-311+G(d,p) optimization, and ropt (2) = MP2/6-311+G(3df,3pd) optimization.     Calc. (1) Calc. (2)   Expt. [1]     Xaa - 1566.5 - 1541.1 - 1550.634(13) Xbb   789.2   779.3   779.401(12) Xcc   777.3   761.9   771.233(17) Xab   481.3   482.6   497.892(35) * Xac   450.3   456.7   452.170(28) * Xbc   - 86.9   - 89.3     92.25(7) *   RMS 11.3 (1.10 %)   7.7 (0.74 %) RSD 15.2 (1.23 %) 15.2 (1.23 %)   Xxx   860.6   848.9   856.121(20) Xyy   883.9   875.8   881.337(18) Xzz - 1744.5 - 1724.6 - 1737.458(21) ETA 0.0134 0.0156 0.014513(16) Øz,CI 0.55 0.68
	* Absolute value, the product XabXacXbc is negative [1].
	Table 2.  A-2-Iodobutane   ropt (1) = MP2/6-311+G(d,p) optimization, and ropt (2) = MP2/6-311+G(3df,3pd) structure parameters (Å and degrees).     C  C,1,B1  H,1,B2,2,A1  H,1,B3,2,A2,3,D1,0  C,2,B4,1,A3,3,D2,0  I,2,B5,1,A4,5,D3,0  H,2,B6,1,A5,5,D4,0  C,5,B7,2,A6,1,D5,0  H,5,B8,2,A7,1,D6,0  H,5,B9,2,A8,1,D7,0  H,8,B10,5,A9,2,D8,0  H,8,B11,5,A10,2,D9,0  H,8,B12,5,A11,2,D10,0  H,1,B13,2,A12,5,D11,0      ropt (1)      ropt (2)  B1=1.52309647  B2=1.09439919  B3=1.09539193  B4=1.52710721  B5=2.18633275  B6=1.0940065  B7=1.53283919  B8=1.09645871  B9=1.09450454  B10=1.09388025  B11=1.09529135  B12=1.09280284  B13=1.09211151  A1=110.59000358  A2=109.63487217  A3=114.10860178  A4=109.38550113  A5=110.41269895  A6=112.13185788  A7=109.14581552  A8=109.04493074  A9=110.07532588  A10=110.85224216  A11=111.94756036  A12=111.42203348  D1=119.73776402  D2=-56.5742852  D3=122.73406089  D4=-124.30070661  D5=-61.9440144  D6=60.37450553  D7=176.81988378  D8=-172.75903904  D9=-53.53019543  D10=67.4990844  D11=-177.22470697  B1=1.51780948  B2=1.08987151  B3=1.0904817  B4=1.5217983  B5=2.1531448  B6=1.08953756  B7=1.52656517  B8=1.09198305  B9=1.08998223  B10=1.08874766  B11=1.09042816  B12=1.088049  B13=1.0873434  A1=110.48096854  A2=109.79529439  A3=113.84850095  A4=109.27092778  A5=110.5442137  A6=112.00860522  A7=108.87480613  A8=109.0147075  A9=110.26929846  A10=110.93266339  A11=111.86078219  A12=111.31140027  D1=119.74975035  D2=-56.36310512  D3=122.25921707  D4=-124.42416352  D5=-62.6355935  D6=59.61182873  D7=175.90523498  D8=-173.92179995  D9=-54.54315697  D10=66.30418441  D11=-176.86966055
	Table 3.  A-2-Iodobutane.  Rotational Constants (MHz).  ropt (1) = MP2/6-311+G(d,p) and ropt (2) = MP2/6-311+G(3df,3pd) optimization.   ropt(1) ropt(2)    Expt. [1]   A  6370.  6428. 6276.104(8) B  1186.  1213. 1200.61256(18) C  1040.  1063. 1049.42041(11)
	[1] E.A.Arsenault, D.A.Obenchain, Y.J.Choi, T.A.Blake, S.A.Cooke, and S.E.Novick, J.Phys.Chem. A, 120,7145(2016).
	E.A.Arsenault, Y.J.Choi, D.A.Obenchain, S.A.Cooke, T.A.Blake, and S.E.Novick, Abstract WE01, 71st International Symposium on Molecular Spectroscopy, Champaign-Urbana, Ill 2016.
	CH3CH2I		CH3I	2-Iodopropane		1-Iodobutane
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	Molecules/Iodine
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						Last Modified 26 Sept 2016