(CH3)2CN2



















 





 





Nitrogen


Nuclear Quadrupole Coupling Constants


in Dimethyldiazirine



 








 








The rotational spectra of (CH3)2NH2 and (CD3)2NH2 were assigned by Wollrab et al. [1].  Rotational constants, dipole moments, and nuclear quadrupole coiupling constants were measured.


 









Calculation of the 14N nqcc's in methyldiazirine was made here on molecular structures given by MP2/6-311+G(3df,3pd) and MP2/aug-cc-pVTZ optimization.  These are compared with the experimental values in Tables 1 and 2.  Structure parameters are given in Table 3.  Rotational constants and dipole moments are compared in Table 4.












In Tables 1 and 2, RMS is the root mean square difference between calculated and experimental diagonal 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 efg's/nqcc's.






















   









Table 1.  Nitrogen nqcc's in (CH3)2CN2 (MHz).  Calculation was made on (1) MP2/6-311+G(3df,3pd) and (2) MP2/aug-cc-pVTZ optimized molecular structures.

   












Calc (1)

Calc (2)
Expt [1]
   









14N Xaa -
1.438
-
1.428
-
0.94 0.8


Xbb
3.635

3.623

3.20 0.4


Xcc -
2.197
-
2.195
-
2.27 0.4


Xac 0.623
0.621















RMS
0.38 (18 %)

0.38 (18 %)




RSD
0.030 (1.3 %)
0.030 (1.3 %)



 









 








 









   









Table 2.  Nitrogen nqcc's in (CD3)2CN2 (MHz).  Calculation was made on (1) MP2/6-311+G(3df,3pd) and (2) MP2/aug-cc-pVTZ optimized molecular structures.

   












Calc (1)

Calc (2)
Expt [1]
   









14N Xaa -
1.438
-
1.428 -
1.21 0.8


Xbb
3.635

3.623
3.44 0.4


Xcc -
2.197
-
2.195 -
2.23 0.4


Xac 0.623
0.621















RMS
0.18 (7.6 %)

0.17 (7.2 %)




RSD
0.030 (1.3 %)
0.030 (1.3 %)



 









 









 


Table 3.  (CH3)2CN2:  ropt(1) = MP2/6-311+G(3df,3pd) and ropt(2) = MP2/aug-cc-pVTZ optimized molecular structure parameters ( and degrees).
 



 C
 N,1,B1
 N,2,B2,1,A1
 C,1,B3,2,A2,3,D1,0
 H,4,B4,1,A3,2,D2,0
 H,4,B5,1,A4,2,D3,0
 H,4,B6,1,A5,2,D4,0
 C,1,B7,2,A6,3,D5,0
 H,8,B8,1,A7,2,D6,0
 H,8,B9,1,A8,2,D7,0
 H,8,B10,1,A9,2,D8,0






     ropt(1)      ropt(2)
 




 B1=1.47664575
 B2=1.25261793
 B3=1.49714309
 B4=1.09055023
 B5=1.09055023
 B6=1.08787932
 B7=1.49714309
 B8=1.09055023
 B9=1.09055023
 B10=1.08787932
 A1=64.9035695
 A2=117.42745861
 A3=110.51632799
 A4=110.51632799
 A5=110.80489382
 A6=117.42745861
 A7=110.51632799
 A8=110.51632799
 A9=110.80489382
 D1=-104.06713796
 D2=148.80533504
 D3=-91.71432158
 D4=28.54550673
 D5=104.06713796
 D6=91.71432158
 D7=-148.80533504
 D8=-28.54550673
 B1=1.47997225
 B2=1.25421414
 B3=1.49696888
 B4=1.09124025
 B5=1.09124025
 B6=1.0883909
 B7=1.49696888
 B8=1.09124025
 B9=1.09124025
 B10=1.0883909
 A1=64.92976404
 A2=117.40769957
 A3=110.52477633
 A4=110.52477633
 A5=110.78247549
 A6=117.40769957
 A7=110.52477633
 A8=110.52477633
 A9=110.78247549
 D1=-104.03796195
 D2=148.7751279
 D3=-91.75609665
 D4=28.50951562
 D5=104.03796195
 D6=91.75609665
 D7=-148.7751279
 D8=-28.50951562



 








 








 



Table 4.  (CH3)2CN2:  ropt(1) = MP2/6-311+G(3df,3pd) and ropt(2) = MP2/aug-cc-pVTZ  rotational constants (MHz) and B3PW91/6-311+G(df,pd) dipole moments (D).
 





 ropt(1) ropt(2) Expt [1]






A
 7154.
 7150.
7137.16

B
 6054.
 6039.
6015.88

C
 4015.
 4009.
3975.08






   2.35
 2.35
2.19(7)


 








 








[1]  J.E.Wollrab, L.H.Scharpen, D.P.Ames, and J.A.Merritt, J.Chem.Phys. 49,2405(1968).


 








 








Diazarine
Methyldiazirine
Chloromethyldiazirine






















Table of Contents




Molecules/Nitrogen




 








 













CH32CN2.html






Last Modified 9 Jan 2017