OC2H3CN




 








Nitrogen


Nuclear Quadrupole Coupling Constants


in Oxiranecarbonitrile


 







 
 
Calculation of the nitrogen nqcc's in oxiranecarbonitrile was made on a structure obtained by MP2/6-311+G(d,p) optimization with correction of the CN bond length as discussed below.  These are compared in Table 1 with the experimental nqcc's of Müller and Bauder [1].  Structure parameters are given in Table 2, atomic coordinates in Table 3, and rotational constants in Table 4.
 
In Table 1, 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 the nitrogen nqcc's.
 
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.
 
 
   







Table 1. Nitrogen nqcc's in OC2H3CN (MHz).  Calculation was made on the MP2/6-311+G(d,p) optimized structure (as discussed below).
   










Calc.
Expt. [1]
   






14N Xaa - 3.743 - 3.725(13)
Xbb 2.016 2.010(14)
Xcc 1.727 1.715(15)
Xab 0.072 *
Xac - 1.988 *
Xbc 0.252 *
 
RMS 0.013 (0.53 %)
RSD 0.030 (1.3 %)
 
Xxx 1.916
Xyy 2.477
Xzz - 4.393
ETA 0.128
Øz,a 18.09
Øz,b 91.31
Øz,c 71.96
Øz,CN   0.21
 
 
* The algebraic signs of the off-diagonal components depend upon the orientation of the molecule with respect to a,b,c axes.  Here, the algebraic signs correspond to the atomic a,b,c coordinates given in Table 3.
 
 
Molecular Structure
 
The structure parameters given below are those obtained by optimization at the MP2/6-311+G(d,p) level of theory, with the exception of the CN bond length.  The CN bond length is corrected, according to the method of Demaison et al. [2].
 
Table 2.  Molecular structure parameters, MP2/6-311+G(d,p), ropt (Å and degrees).
 
OC(1) 1.4324
Z-Matrix OC(2) 1.4328
C(1)C(2) 1.4746
C(1)H 1.0860
C(1)C 1.4504
CN 1.1566
C(2)Hc 1.0859
C(2)Ht 1.0859
C(1)CN 179.62
OC(2)C(1)   59.01
CC(1)H 115.21
HcC(2)Ht 117.23
 
 
Table 3.  Oxiranecarbonitrile.  Atomic coordinates, ropt.
(More figures are shown than are significant.)
 
  a (Å)   b (Å)   c (Å)
O 1.235984 - 0.706984 - 0.258562
C 0.306180 - 0.012321 0.580883
C 1.340538 0.719460 - 0.173469
C - 1.070945 0.012098 0.126359
N - 2.171134 0.035102 - 0.229698
H 0.438826 - 0.175096 1.646390
H 2.208398 1.088804 0.364659
H 1.047666 1.255084 - 1.071529
 
 
Table 4. Oxiranecarbonitrile.  Rotational constants (MHz).
Calc., ropt       Expt. [1]
A 18 395.3 18 456.2955(29)
B   3 520.7   3 524.70497(46)
C   3 365.8   3 367.81108(42)
 
 
[1] F.Müller and A.Bauder, J.Mol.Spectrosc. 179,61(1996).
[2] J.Demaison, J.Cosléou, R.Bocquet, and A.G.Lesarri, J.Mol.Spectrosc. 167,400(1994).

 








 








HCCCN CH3CN (CH3)3CCN
C6H5CN CH2CHCN
 

 








Table of Contents



Molecules/Nitrogen
 

 













C3H3NO.html






Last Modified 15 Nov 2005