CH3CN






 









Deuterium and Nitrogen


Nuclear Quadrupole Coupling Constants


in Methyl Cyanide


 








 


 





Deuterium nqcc's in fully deuterated methyl cyanide were determined by Murray and Kukolich [1].  A number of measurements of the nitrogen nqcc in the normal species have been reported [1 - 8].  Deuterim and nitrogen nqcc's have been determined in the d1 species by Merke et al. [9].  LeGuennec et al. [10] determined an equilibrium structure.

 








Calculation of the deuterium and nitrogen nqcc's was made here on the equilibrium structure.  These nqcc's are compared with the experimental values in Tables 1 -3.  Structure parameters and atomic coordinates respectively are given in Tables 4 and 5.

 








 








Coordinate Systems

Subscripts u,v,w refer to the coordinate axes defined in Table 4.  The u-axis is along the threefold symmetry axis.  The nqcc's given below with these subscripts are those for the D atom in the uv-plane.

Subscripts a,b,c refer to the principal inertial axis.

Subscripts x,y,z refer to the principal axes of the nqcc tensor.  The y-axis is chosen coincident with the w-axis.  (degrees) is the angle between its subscripted parameters.  ETA = (Xxx - Xyy)/Xzz.

RMS is the root mean square difference between calculated and experimental diagonal nqcc's.  RSD is the residual standard deviation of calibration of the models for calculation of the nqcc's.

 








 








   







Table 1.  Deuterium nqcc's in CD3CN (kHz).

 









Calc.
Expt. [1]

 







2H Xuu
- 56.2
- 55.1(4)


Xvv
153.6



  Xww
- 97.4




Xuv
- 90.6



 







RSD
1.1 (0.86 %)



 







Xxx
- 89.8




Xyy
- 97.4




Xzz
187.2




ETA
0.040




z,u
69.60




u,CD
69.90




z,CD
  0.30




 






 








 








   







Table 2.  Nitrogen nqcc's in CH3CN (MHz).

 









Calc.
Expt. [1 - 8]
   







14N Xzz - 4.208 - 4.22410(98) [2]

 


- 4.2292(6) [1]





- 4.22534(73) [3]





- 4.22473(80) [4]





-
4.22497(42) [5]






- 4.214(16) [6]





- 4.2244(15) [7]





-
4.22324(108) [8]


 







 








The difference between calculated and experimental [1-3] 14N nqcc's is 16-21 kHz (0.4 - 0.5 %).

 








 








   







Table 3.  Deuterium (kHz) and Nitrogen (MHz) nqcc's in CH2DCN.

 









Calc.
Expt. [9]

 







2H Xaa
- 50.3
- 56.2(54)


Xbb
147.7
151.6(51)

  Xcc
- 97.4
- 95.4(52)


|Xab|
  96.9



 







RMS
4.2 (4.2 %)




RSD
1.1 (0.86 %)




 





14N Xaa - 4.202 - 4.2183(23)


Xbb
2.098
2.1100(30)


Xcc
2.104
2.1083(29)


|Xab|
0.197



 







RMS
0.012 (0.42 %)




RSD
0.030 (1.3 %)



   






 








 


 
Table 4. Structure parameters, re [10] ( and degrees).
 






CH 1.087



CC 1.457



CN 1.156



HCC 110.1


 
















Table 5. Atomic coordinates, re
(More figures are shown than are significant.)
 









  u ()
  v ()
  w ()
 







H - 1.550012
1.020795
0.0

H - 1.550012 - 0.510398 0.884035

C - 1.176454
0.0
0.0

C
0.280546
0.0
0.0

N
1.436546
0.0
0.0


 








 








[1] A.M.Murray and S.G.Kukolich, J.Chem. Phys. 78,3557(1983).

[2] M.Simeckova, S.Urban, U.Fuchs, F.Lewen, G.Winnewisser, I.Morino, and K.M.T.Yamada, J.Mol.Spectrosc. 226,123(2004).

[3] D.Boucher, J.Burie, J.Demaison, A.Dubrille, J.Legrand, and B.Segard, J.Mol.Spectrosc. 64,290(1977).

[4] G.Cazzoli and C.Puzzarini, J.Mol.Spectrosc. 240,153(2006).  Corrigendum: 247,187(2008).

[5] J.C.Pearson and H.S.P.Mller, Astrophys.J. 471,1067(1996).

[6] M.K.Kemp, J.M.Pochan, and W.H.Flygare, J.Phys.Chem. 71,765 (1967).

[7] S.G.Kukolich, D.J.Ruben, J.H.S.Wang, and J.R.Williams, J.Chem.Phys. 58(8),3155(1973).

[8] H.S.P.Mller, B.J.Drouin, and J.C.Pearson, A&A 506,1487(2009).


[9] I.Merke, W.Stahl, and H.Dreizler, Z.Naturforsch. 49a,490(1994).

[10] M.LeGuennec, G.Wlodarczak, J.Burie, and J.Demaison, J.Mol. Spectrosc. 154,305(1992).

 








J.Demaison, A.Dubrille, D.Boucher, J.Burie, and V.Typke, J.Mol.Spectrosc. 76,1(1979):  rz structure.

C.Puzzarini and G.Cazzoli, J.Mol.Spectrosc. 240,260(2006):  Semi-experimental re structures; and  (all)CCSD(T)/cc-pwCVQZ calculation of eQq, which gives -4.22 MHz.

I.An, W.M.Rhee, and J.A.Roberts, J.Chem.Phys. 86,4725 (1987):  eQq = -4.54667 MHz


 








 








CH2(CN)2 CF3CN SiH3CN GeH3CN

CH2Cl2 CHCl3 CH3Br CH2Br2

CH3F CH2F2 CHF3 CH3D

CH2FCN CHF2CN CHCl3


 








 








Table of Contents




Molecules/Nitrogen




Molecules/Deuterium




Summary/Methyls  Deuterium nqcc's in the substituted methanes.

 








 













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Last Modified 13 Nov 2011