3-CN-C4H3S





 














 






 








Nitrogen

Nuclear Quadrupole Coupling Constants


in 3-Cyanothiophene


 








 








Calculation of the nitrogen nqcc tensor in 3-cyanothiophene was made here on molecular structures given by B3PW91/6-31G(2d,2pd) and B3P86/6-31G(3d,3p) optimization.  Calculated and (limited) experimental nqcc's are compared 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 inertia c-axis, these are perpendicular to the plane of the molecule.  Ø (degrees) is the angle between its subscripted parameters. ETA = (Xxx - Xyy)/Xzz.  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.  14N nqcc's in 3-Cyanothiophene (MHz).

 







Calculation was made on


the [a] B3PW91/6-31G(2d,2pd) opt structure, and


the [b] B3P86/6-31G(3d,3p) opt structure.
   









Calc. [a]
Calc. [b]
Expt. [1]
   







Xaa -
 4.157
 -
 4.164
 -
 4.12(6)

Xbb
2.355
2.360



Xcc
1.802
1.804



|Xab|
0.584
0.589



 







RSD
0.030 (1.3 %)
 0.030 (1.3 %)


 







Xxx
2.407
2.412



Xyy
1.802
1.804



Xzz -
 4.209
 -
 4.217



ETA -
 0.144
 -
 0.144



Øz,a
5.08
5.12



Øa,CN
4.92
4.96



Øz,CN
0.16
0.16



 








 








 




Table 2.  3-Cyanothiophene.  Optimized structure parameters (Å and degrees).
 






 C
 C,1,B1
 C,2,B2,1,A1
 C,3,B3,2,A2,1,D1,0
 S,1,B4,2,A3,3,D2,0
 H,1,B5,2,A4,3,D3,0
 H,2,B6,1,A5,5,D4,0
 H,4,B7,3,A6,2,D5,0
 C,3,B8,2,A7,1,D6,0
 N,9,B9,4,A8,3,D7,0








B3PW91/6-31G(2d,2pd)
 B3P86/6-31G(2d,3p)








 B1=1.36168749
 B2=1.42946089
 B3=1.37527278
 B4=1.72117647
 B5=1.0785274
 B6=1.08025912
 B7=1.07813504
 B8=1.42422097
 B9=1.15927519
 A1=112.145266
 A2=112.60265368
 A3=111.71673461
 A4=128.39526818
 A5=124.3200165
 A6=127.83800569
 A7=124.01326155
 A8=152.62599636
 D1=0.
 D2=0.
 D3=180.
 D4=180.
 D5=180.
 D6=180.
 D7=180.
  B1=1.36241701
 B2=1.42772759
 B3=1.37643027
 B4=1.71286044
 B5=1.07987378
 B6=1.08165947
 B7=1.07953269
 B8=1.42110302
 B9=1.15839262
 A1=111.92855869
 A2=112.53909188
 A3=111.79343415
 A4=128.17706297
 A5=124.40165197
 A6=127.55708554
 A7=124.05859004
 A8=152.59196947
 D1=0.
 D2=0.
 D3=180.
 D4=180.
 D5=180.
 D6=180.
 D7=180.








 























Table 3.  3-Cyanothiophene.  Rotational Constants (MHz).
   



[a] B3PW91/6-31G(2d,2pd) opt structure.

[b] B3P86/6-31G(3d,3p) opt structure.
 





Calc [a] Calc [b] Expt. [1]






A
  7125.
  7150.
 7115.180(13)

B
  1493.
  1499.
 1491.299(2)

C
  1234.
  1239.
 1232.535(2)



  








[1] J.Wiese and D.H.Sutter, Z.Naturforsch. 32a,890(1977).

 








J.Wiese, R.Schwarz, and D.H.Sutter, Z.Naturforsch. 35a,770(1980).

 








 








Thiophene 2-Cyanofuran 2-Bromothiophene

3-Chlorothiophene 3-Bromothiophene 2-Chlorothiophene

2-Cyanothiophene






 








Table of Contents




Molecules/Nitrogen




 








 













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Last Modified 21 Dec 2015