CH2(CN)-C(=O)H
































 









Nitrogen


Nuclear Quadrupole Coupling Constants


in Cyanoacetaldehyde


 








 


 





Calculation of the nitrogen nqcc's in cyanoacetaldehyde (conformer I, Ref. [1]) was made on an approximate equilibrium structure derived here by MP2/aug-cc-pVTZ(G03) optimization with empirical correction for the bond lengths (~ re).  These calculated nqcc's are given in Table 1.  Structure parameters are given in Table 2.












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.  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 nqcc's, which may be taken as an estimate of the uncertainty in the calculated nqcc's.

 








 








   







Table 1.  Nitrogen nqcc's in Cyanoacetaldehyde (MHz).  Calculation was made on the ~ re structure.

   








Calc.
Expt.

 







14N Xaa - 2.988




Xbb
0.937



  Xcc
2.051




Xab
2.632




Xac
0.300





Xbc -
0.299




 







RSD
0.030 (1.3 %)



 







Xxx
2.006




Xyy
2.327




Xzz - 4.333




ETA
0.074




Øz,CN
  0.64



 







 








 












Table 2.  CH2(CN)-C(=O)H  Heavy atom structure parameters, ~ re (Å and degrees).  The complete strcucture is given here in Z-matrix format.
 



O(1)C(2)
1.2025
C(2)C(3)
1.5208
C(3)C(4)
1.4575
C(4)N(5)
1.1559
O(1)C(2)C(3)
122.34
C(2)C(3)C(4)
111.47
C(3)C(4)N(5) *
177.58
Click on image to enlarge. O(1)C(2)C(3)C(4)
-
144.76
  * N tilts toward C(2)H(6)


 








 








 








[1] H.Møllendal, L.Margulès, R.A.Motiyenko, N.W.Larsen, and J.-C.Guillemin, J.Phys.Chem. A 116,4047(2012).


 








 








Propargl Cyanide Acetyl Cyanide Cyanoacetaldehyde, sp


 








 








Table of Contents




Molecules/Nitrogen




 








 













NCCH2COH.html






Last Modified 9 April 2012