p-CH3-C6H4-I




 






















 








Iodine

Nuclear Quadrupole Coupling Constants


in p-Iodotoluene


 








 








 

 





Iodine nqcc's were calculated here on a molecular structure determined by B3P86 and  PBE1PBE optimization each with 6-31G(3d,3p) bases on C and H, and 6-311G(3d) basis on I; assuming a plane of symmetry perpendicular to the plane of the ring.  These are compared with the experimental nqcc's [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.  The nqcc y-axis is chosen coincident with the inertial b-axis, these are perpendicular to the symmetry plane of the molecule.  Ø (degrees) is the angle between its subscripted parameters.  ETA = (Xxx - Xyy)/Xzz.

RMS is the root mean square difference between calculated and experimental diagonal nqcc's.  RSD is the calibration residual standard deviation for the B1LYP/6-311G(df,p) model for calculation of the nqcc's.

 








 








   







Table 1.  Iodine nqcc's in p-Iodotoluene (MHz).  Calculation was made on the (1)  B3P86 and (2) PBE1PBE ropt structures.
   










Calc (1)
Calc (2)
Expt. [1]
   







127I Xaa -
 1886.1 -
 1883.0
 -
 1886.202(12)


Xbb
  979.6
  978.6
  972.291(18) *


Xcc
  906.5
  904.4
  913.911(18) *


|Xac|
      2.7
      2.7


 








RMS
  6.0 (0.48 %)
  6.9 (0.55 %)



RSD
15.2 (1.23 %)
15.2 (1.23 %)


 







  Xxx
  979.6
  978.6
  972.291(18)


Xyy
  906.5
  904.4
  913.911(18)


Xzz -
 1886.1 -
 1883.0
 -
 1886.202(12)


ETA -
 0.0387 -
 0.0394



Øz,a
0.056
0.056



Øa,CI
0.046
0.046



Øz,CI
0.010
0.010


 








 








* Calculated here from experimental Xaa and Xbb - Xcc = 58.380(34) MHz.

 








 

Table 2.  p-Iodotoluene.  Molecular structure parameters, ropt(1) = B3P86 and ropt(2) = PBE1PBE (Å and degrees).




 C
 C,1,B1
 C,2,B2,1,A1
 C,3,B3,2,A2,1,D1,0
 C,4,B4,3,A3,2,D2,0
 C,1,B5,2,A4,3,D3,0
 H,1,B6,6,A5,5,D4,0
 H,2,B7,1,A6,6,D5,0
 H,4,B8,3,A7,2,D6,0
 H,5,B9,4,A8,3,D7,0
 C,6,B10,1,A9,2,D8,0
 H,11,B11,6,A10,1,D9,0
 H,11,B12,6,A11,1,D10,0
 H,11,B13,6,A12,1,D11,0
 I,3,B14,2,A13,1,D12,0
 
         ropt(1)        ropt(2)
 B1      1.38973978
 B2      1.3898615
 B3      1.3898615
 B4      1.38973978
 B5      1.39523138
 B6      1.08650083
 B7      1.08361947
 B8      1.08361947
 B9      1.08650083
 B10    1.50138625
 B11    1.09266659
 B12    1.09562381
 B13    1.09266659
 B14    2.11120594
 A1      119.25101486
 A2      120.53514672
 A3      119.25101486
 A4      121.53960622
 A5      119.50736048
 A6      120.22982799
 A7      120.51884667
 A8      118.95286307
 A9      121.05418889
 A10    111.40571458
 A11    110.99234492
 A12    111.40571458
 A13    119.73210445
 D1          0.12050211
 D2         -0.12050211
 D3          0.07709446
 D4      179.58303799
 D5      179.87545555
 D6      179.67726196
 D7      179.77203048
 D8      178.6751156
 D9      150.99293479
 D10    -89.45335253
 D11     30.10036016
 D12   179.82770828
 B1     1.38949925
B2     1.38982042
B3     1.38982042
B4     1.38949925
B5     1.39507874
B6     1.08725837
B7     1.08438228
B8     1.08438228
B9     1.08725837
B10   1.50102761
B11   1.09324796
B12   1.09619542
B13   1.09324796
B14   2.10802225
A1     119.26728058
A2     120.51224647
A3     119.26728058
A4     121.52874473
A5     118.97391291
A6     120.25361657
A7     120.47879840
A8     118.97391291
A9     121.04813412
A10   111.40748023
A11   110.95991790
A12   111.40748023
A13   119.74355672
D1         0.11993599
D2        -0.11993599
D3        -0.07430503
D4    -179.77277551
D5     179.87455316
D6     179.67985164
D7     179.77277551
D8    -178.68134322
D9      -30.08619201
D10     89.45363560
D11  -151.00653678
D12   179.82814942



 







 
 



Table 3.  p-Iodotoluene.  Rotational constsnts.  ropt(1) = B3P86 and ropt(2) = PBE1PBE.
   




ropt(1) ropt(2) Expt [1]

 



A
 5557.7
 5558.0
 5707.01(13)

B
   487.8
   488.5
   490.054574(54)

C
   449.7
   450.3
   451.316364(54)

 





 








 








[1] V.A.Shubert, D.Schmitz, and M.Schnell, Mol.Phys. 111,2189(2013).

 








 








p-Chlorotoluene Iodobenzene

p-Bromotoluene

 








 








Table of Contents





Molecules/Iodine




 








 













4IodoToluene.html






Last Modified 5 Aug 2013