(CH3)2-N-CH2CH2OH







































 









Nitrogen


Nuclear Quadrupole Coupling Constants

in 2-Dimethylaminoethanol


 








 








 


 





The microwave spectrum of 2-dimethylaminoethanol was investigated by Penn and Birkenmeier [1].


Calculation of the 14N nuclear quadrupole coupling constant tensor was made here on ropt molecular structures given by MP2/6-311++G(d,p) and MP2/6-311+G(df,pd) optimization.


 








Calculated nitrogen nqcc's are given in Table 1, rotational constants and electric dipole moments in Table 2.  Optimized structure parameters are given here in Z-Matrix format.


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.  ETA = (Xxx - Xyy)/Xzz.  Øz,C(8)N  is angle between the z-principal axes of the nqcc tensor and the C(8)N bond axis.  RSD is the calibration residual standard deviation of the B3PW91/6-311+G(df,pd) model for calculation of the efg's/nqcc's. 


 








 








   








Table 1.  14N nqcc's in 2-Dimethylaminoethanol (MHz).  Calculation was made on (1) MP2/6-311++G(d,p) and (2) MP2/6-311+G(df,pd) ropt structures.

   










Calc (1)
Calc (2)

Expt

   








Xaa
0.917

0.905




Xbb
2.505

2.521




Xcc -
3.422
-
3.426




Xab
0.457

0.413




Xac
3.156

3.157




Xbc -
0.870
-
0.781




 







RSD
0.030 (1.3 %)
0.030 (1.3 %)



 








Xxx
2.630
2.622




Xyy
2.578

2.568




Xzz -
5.208
-
5.190




ETA
-
0.010
-
0.010




Øz,C(8)N

107.7

107.6














 








 








 





Table 2.  2-Dimethylaminoethanol. Rotational Constants (MHz) and Dipole Moments * (D).  ropt(1) = MP2/6-311+G(d,p), ropt(2) = MP2/6-311+G(df,pd).

 





ropt(1) ropt(2)   Expt [1]

 




 A
5803
5829
5814.0(2)

 B
2233
2261
2214.54(2)

 C
2054
2083
2037.96(2)

a| 2.48
2.48
2.27(2)

b| 0.47
0.40
0.3(1)

c| 1.26
1.29
1.16(5)

tot| 2.82
2.83
2.56

 




* Calculated by B3PW91/6-311+G(df,pd) method on MP2 ropt structures.



 








 









[1] R.E.Penn and J.A.Birkenmeier, J.Mol.Spectrosc. 62,416(1976).


 









 








Dimethylamine Diethylamine
Methylaminoethane
2-Methylaminoethanol

 









 









Table of Contents




Molecules/Nitrogen




 








 













DMAE.html






Last Modified 27 Dec 2013