CH3-CHI-CH2-CH3






 








 








Iodine

Nuclear Quadrupole Coupling Constants


in 2-Iodobutane G'


 








G
A
G'
























Click on G, A to view results for these conformers.











Calculation of the iodine nqcc tensor in the G' 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 G'-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 -
 1274.6
 -
 1241.8
 -
 1256.176(6)

Xbb
  580.9
  563.7
  569.007(11)

Xcc
  693.7
  678.1
  687.169(12)

Xab
  784.1
  789.2
  792.17(4) *

Xac
  615.8
  619.0
  615.34(6) *

Xbc
- 224.4
- 229.2
  227.51(4) *

 







RMS
  9.8 (1.18 %)
 10.3 (1.23 %)


RSD
15.2 (1.23 %) 15.2 (1.23 %)



 







Xxx
  867.5
  857.0
  867.14(5)

Xyy
  870.6
  862.8
  862.95(4)

Xzz -
 1738.1
 -
 1719.8
 -
 1730.09(4)

ETA
0.0017
0.0034
 -
 0.00242(4)

Øz,CI
0.46
0.36



 








 








* Absolute value, the product XabXacXbc is negative [1].

 








 

Table 2.  G'-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=1.52310023
 B2=1.09223902
 B3=1.09759538
 B4=1.52861697
 B5=2.18947412
 B6=1.09263375
 B7=1.52758481
 B8=1.09477801
 B9=1.10004137
 B10=1.09365685
 B11=1.0932972
 B12=1.09335379
 B13=1.09234953
 A1=111.75825536
 A2=108.68852526
 A3=114.10686128
 A4=109.79741483
 A5=109.87777404
 A6=115.37472811
 A7=109.18483904
 A8=105.96852971
 A9=110.07310062
 A10=111.59827742
 A11=110.97858872
 A12=111.14984883
 D1=119.69869094
 D2=-65.79225693
 D3=125.39095308
 D4=-122.76559199
 D5=55.84106123
 D6=-179.78548805
 D7=-65.14030314
 D8=178.01891734
 D9=-62.52409799
 D10=58.46838694
 D11=173.30791606
  B1=1.51785477
 B2=1.08769552
 B3=1.09262469
 B4=1.52336002
 B5=2.15648335
 B6=1.08813492
 B7=1.52156264
 B8=1.09033412
 B9=1.09510242
 B10=1.08850508
 B11=1.08841388
 B12=1.08916027
 B13=1.08754587
 A1=111.46803697
 A2=109.00439881
 A3=113.94605993
 A4=109.6367409
 A5=110.0430286
 A6=115.03692124
 A7=109.01387852
 A8=106.22312037
 A9=110.24015007
 A10=111.56105514
 A11=110.8618978
 A12=111.08401858
 D1=119.73797684
 D2=-65.04369414
 D3=124.70453539
 D4=-123.08429058
 D5=56.95360797
 D6=-179.05009639
 D7=-64.18469321
 D8=178.33309543
 D9=-62.04576769
 D10=58.73605952
 D11=174.2901898





 























Table 3.  G'-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  4491.
  4507.
 4433.8638(7)

B  1491.
  1541.
 1520.53128(26)

C  1272.
  1309.
 1287.89606(38)



  








 








[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 CH3I2-Iodopropane
1-Iodobutane


 








 








Table of Contents




Molecules/Iodine




 








 













2_Iodobutane_G_prime.html






Last Modified 26 Sept 2016