CH2=N-CH2CN































 









Nitrogen


Nuclear Quadrupole Coupling Constants

in Methyleneaminoacetonitrile

 








 


















Millimeter- and submillimeter-wave spectrum of methyleneaminoacetonitrile were observed by Motiyenko et al. [1].  Quadrupole hyperfine structure, however, was not resolved.

 

 





Calculation of the nitrogen nqcc's was made here on ropt molecular structures given by MP2/6-311+G(3df,3pd) and MP2/aug-cc-pVTZ optimization, each with corrected CN bond lengths.

 








These calculated nqcc's are shown in Tables 1 and 2, structure parameters in Table 3, rotational constants in Table 4.

In Tables 1 and 2, 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.  Ø (degrees) is the angle between its subscripted parameters.  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. Imine 14N nqcc's in CH2=N-CH2CN (MHz).  Calculation was made on the (1) MP2/6-311+G(3df,3pd) and (2) MP2/aug-cc-pVTZ ropt structures, each with corrected CN bond lengths.
   









Calc (1)
Calc (2)
Expt
   







Xaa -
 1.703
 -
 1.719



Xbb -
 1.277
 -
 1.243



Xcc
2.980
2.962



Xab
3.316
3.305



 







RSD
0.030 (1.3 %)
0.030 (1.3 %)



 







Xxx
1.833
1.832



Xyy
2.980
2.962



Xzz -
 4.813
 -
 4.794



ETA
0.238
0.236



Øz,a
43.16
42.94



Øa,bi*
30.07
29.81



Øz,bi
13.09
13.12



 








 








* "bi" is bisector of CNC angle.

 








 








   







Table 2. Cyano 14N nqcc's in CH2=N-CH2CN (MHz).  Calculation was made on the (1) MP2/6-311+G(3df,3pd) and (2) MP2/aug-cc-pVTZ ropt structures, each with corrected CN bond lengths.
   









Calc (1)
Calc (2)
Expt
   







Xaa -
 1.877
 -
 1.859



Xbb -
 0.078
 -
 0.097



Xcc
1.955
1.956



Xab
3.281
3.284



 







RSD
0.030 (1.3 %)
0.030 (1.3 %)



 







Xxx
2.424
2.422



Xyy
1.955
1.956



Xzz -
 4.379
 -
 4.378



ETA
 -
 0.107
 -
 0.106



Øz,a
37.33
37.49



Øa,CN
38.61
38.86



Øz,CN
  1.28
  1.37



 








 












Table 3.  CH2=N-CH2CN MP2/6-311+G(3df,3pd) and MP2/aug-cc-pVTZ optimized structure parameters.  Corrected approximate equilibrium CN bond lengths are given in parentheses.  (Å and degrees).





 C
 C,1,B1
 H,2,B2,1,A1
 H,2,B3,1,A2,3,D1,0
 N,2,B4,1,A3,4,D2,0
 C,5,B5,2,A4,1,D3,0
 N,1,B6,2,A5,5,D4,0
 H,6,B7,5,A6,2,D5,0
 H,6,B8,5,A7,2,D6,0


MP2/6-311+G(3df,3pd) MP2/aug-cc-pVTZ




 B1=1.46765458
 B2=1.08947342
 B3=1.08947342
 B4=1.45719663
 B5=1.27256488
 B6=1.16993766  (1.1564)
 B7=1.08339773
 B8=1.09147309
 A1=109.00486088
 A2=109.00486088
 A3=115.80257584
 A4=119.08824433
 A5=176.11265378
 A6=117.64792811
 A7=123.99444427
 D1=116.4968565
 D2=121.75157175
 D3=0.
 D4=0.
 D5=180.
 D6=0.
  B1=1.46713554
 B2=1.09005041
 B3=1.09005041
 B4=1.45887312
 B5=1.27425494
 B6=1.17136501  (1.1564)
 B7=1.0837784
 B8=1.09218571
 A1=109.03766591
 A2=109.03766591
 A3=115.67398477
 A4=118.86237462
 A5=175.84806765
 A6=117.59533762
 A7=124.05162189
 D1=116.51589678
 D2=121.74205161
 D3=0.
 D4=0.
 D5=180.
 D6=0.
 





 













Table 4.  CH2=N-CH2CN Rotational Constants (MHz).  r(1) = MP2/6-311+G(3df,3pd) and r(2) =  MP2/aug-cc-pVTZ, each with corrected CN bond lengths.







  r(1)   r(2)     Expt [1]






A
 12221.
 12165.
 12318.41512(26)

B
   3982.
   3999.
   3912.427270(66)

C
   3059.
   3066.
   3022.364639(55)



 








 








[1]  R.A.Motiyenko, L.Margules, and J.C.Guillemin, A&A 559,A44(2013).

 








 








CH2N=H
 CH2N-CH3 CH3CN



 








 








Table of Contents




Molecules/Nitrogen




 








 













CH2NCH2CN.html






Last Modified 15 June 2016