Thiomorpholine




 SC4H8N-H

















 





 









Nitrogen


Nuclear Quadrupole Coupling Constants

in Thiomorpholine (chair, eq)

 








 








 

 





Calculation of the nitrogen nqcc's in equatorial thiomorpholine (chair) was made here on a molecular structure given by MP2/6-311+G(2d,2p) optimization.  These are compared with the experimental nqcc's [1] in Table 1.  MP2/6-311+G(2d,2p) structure parameters are shown in Table 2, rotational constants in Table 3.

 








In Table 1, subscripts a,b,c refer to the principal axes of the inertia tensor; x,y,z to the principal axes of the nqcc tensor.  The nqcc y-axis is chosen coincident with the inertia b-axis, these are perpendicular to the molecular symmetry plane.  Ø (degrees) is the angle between its subscripted parameters.  ETA = (Xxx - Xyy)/Xzz.

RMS is the root mean square difference between calculated and experimental nqcc's (percentage of the average of the magnitudes of the experimental nqcc's).  RSD is the calibration residual standard deviation of the  B3PW91/6-311+G(df,pd) model for calculation of nitrogen nqcc's.

 








 








   






Table 1.  Nitrogen nqcc's in equatorial Thiomorpholine (MHz).  Calculation was made on the MP2/6-311+G(2d,2p) optimized structure.
   









Calc.
Expt. [1]
   






14N Xaa
2.196
1.74(9)


Xbb
2.837
2.89(26)


Xcc - 5.033
 -
 4.63(35)


|Xac|
0.614



 







RMS
0.35(11 %)
 


RSD
0.030 (1.3 %)



 







Xxx
2.248




Xyy
2.837



  Xzz - 5.085



  ETA
0.116




Øz,a
85.18




Øa,NH






Øz,NH





 







 








 








 







 
 



Table 2.  Equatorial Thiomorpholine (X=S), Morpholine (X=O), and Piperidine (X=CH2).  Selected MP2/6-311+G(2d,2p) ropt structure parameters (Å and degrees).  Complete thiomorpholine structure is given here.
 





 X=S
  X=O  X=C
 




C(1)N 1.4626
 1.4639 1.4637
NH 1.0099
 1.0102 1.0107
C(1)C(2) 1.5182
 1.5162 1.5232
C(2)X(3) 1.8202
 1.4266 1.5284
C(5)NC(1) 112.87
 109.89 111.17
NC(1)C(2) 110.06
 108.14 109.18
C(1)C(2)X(3) 111.81
 110.86 110.21
C(2)X(3)C(4)   96.61
 110.08 110.46



 








 














Table 3.  Thiomorpholine (equatorial, chair).  Rotational Constants (MHz).  Normal Species.
 








 ropt    Expt. [1]









A
 4217.76
 4198.443(7)



B
 3062.31
 3061.117(3)



C
 1965.76
 1901.006(2)


 








 








[1] A.C.Fantoni, R.R.Filgueira, L.M.Boggia, and W.Caminati, J.Mol.Spectrosc. 84,493(1980).

 








 








Piperidine Morpholine



 








 








Table of Contents




Molecules/Nitrogen




 













Thiomorpholine.html






Last Modified 5 Sept 2011