HCOOH


























 






Deuterium


Nuclear Quadrupole Coupling Constants


in trans Formic Acid


 








 








 








Deuterium nqcc's were measured in HC(=O)OD by Ruben and Kukolich [1], and in DC(=O)OH and DC(=O)OD by Cazzoli, et al [2].  An equilibrium structure was determined by Davis, et al [3], and a semi-experimental equilibrium structure by Demaison et al. [4].

 








Calculations of the deuterium nqcc's in these were made on the equilibrium structures.  In Table 1, calculated and experimental deuterium nqcc's in HC(=O)OD are compared.  In Table 2, calculated and experimental deuterium nqcc's in DC(=O)OH are compared.  In Tables 3 and 4, calculated and experimental deuterium nqcc's in DC(=O)OD are compared.  Structure parameters are given in Table 5.

 


 





In Tables 1 - 4, 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 for the model for calculation of the nqcc's. 

Subscripts a,b,c refer to the principal axes of the inertia tensor, subscripts x,y,z to the principal axes of the nqcc tensor.  The nqcc y-axis is chosen coincident with the inertia c-axis, these are perpendicular to the plane of the molecule.  Ø (degrees) is the angle between its subscripted parameters. ETA = (Xxx - Xyy)/Xzz.

 








 








   









Table 1.  Deuterium nqcc's in HC(=O)OD (kHz).  Calculation was made on the re [3] and rese [4] structures.
   












Calc/re
Calc/rese
Expt. [1]
   









OD Xaa - 119.2 - 122.2 - 119.3(20)


Xbb
267.6
273.5
267.5(30)


Xcc - 148.4 - 151.3 - 148.2(20)


|Xab|
  25.6
  24.0



 









RMS
0.2 (0.1 %)
4.3 (2.4 %)




RSD
1.1 (0.9 %)
1.1 (0.9 %)



 









Xxx - 120.8 - 123.7




Xyy - 148.4 - 151.3




Xzz
269.3
275.0




ETA
0.102
0.100




Øz,a
86.23
86.53




Øa,OD
84.85
85.23




Øz,OD
  1.38
  1.30



 









 








 








   









Table 2.  Deuterium nqcc's in DC(=O)OH (kHz).  Calculation was made on the re [3] and rese [4] structures.
   












Calc/re
Calc/rese
Expt [2]

   









CD Xaa
- 86.0
- 84.6
- 80.0(13) *


Xbb
175.2
173.4
171.2(22) *


Xcc
- 89.2
- 88.8
- 91.2(22) *


|Xab|
    6.8
  13.4




 








  RMS

4.3 (3.8 %)

3.2 (2.8 %)





RSD
1.1 (0.9 %)
1.1 (0.9 %)



 









Xxx
- 86.1
- 85.2




Xyy
- 89.2
- 88.8




Xzz
175.4
174.0




ETA
0.018
0.020




Øz,a
88.51
87.04




Øa,CD
88.59
86.70




Øz,CD
  0.07
  0.34



 









 








  * Calculated here from experimental 1.5Xaa = -0.1200(13)  and (Xbb - Xcc)/4 = 0.06562(26) MHz.


 









 








   









Table 3.  Deuterium nqcc's in DC(=O)OD (kHz).  Calculation was made on the re [3] and rese [4] structures.
   












Calc/re
Calc/rese
Expt. [2]
   









OD Xaa - 119.4 - 122.4 - 123.5(24)


Xbb
267.9
273.8
267.9(18)


Xcc - 148.4 - 151.3 - 144.4(18)


|Xab|
  23.2
  22.2



 









RMS
3.3 (1.8 %)
5.3 (2.9 %)




RSD
1.1 (0.9 %)
1.1 (0.9 %)



 









Xxx - 120.8 - 123.7




Xyy - 148.4 - 151.3




Xzz
269.3
275.0




ETA
0.102
0.100




Øz,a
86.58
86.80




Øa,OD
85.21
85.50




Øz,OD
  1.38
  1.30



 





























   









Table 4.  Deuterium nqcc's in DC(=O)OD (kHz).  Calculation was made on the re [3] and rese [4] structures.
   












Calc/re
Calc/rese
Expt. [2]
   









CD Xaa
- 86.1
- 85.2
- 80.3(33)


Xbb
175.4
174.0
170.8(21)


Xcc
- 89.2
- 88.8
- 90.5(21)


|Xab|
    2.1
    4.5



 









RMS
4.3 (3.8 %)
3.5 (3.1 %)




RSD
1.1 (0.9 %)
1.1 (0.9 %)



 









Xxx
- 86.1
- 85.2




Xyy
- 89.2
- 88.8




Xzz
175.4
174.0




ETA
0.018
0.020




Øz,a
89.54
89.00




Øa,CD
89.46
88.66




Øz,CD
  0.07
  0.34



 









 








 












Table 5.  Molecular structure parameters, re [3] and rese [4] (Å and degrees).
 


 
re [3] rese [4]





OH 0.969 0.9662(1)

CH 1.091 1.0920(1)

C=O 1.201 1.1980(1)

CO 1.340 1.3406(1)

OCO 124.80 124.83(1)

HC=O 123.26 125.04(1)

HCO 111.94

COH 106.61 106.97(1)


 








 








[1] D.J.Ruben and S.G.Kukolich, J.Chem.Phys. 60,100(1974);  S.G.Kukolich, J.Chem.Phys. 51,358(1969).

[2] G.Cazzoli, C.Puzzarini, S.Stopkowicz, and J.Gauss, Chem.Phys.Lett. 502,42(2011); Astro.Phys.J. Supp.Series 196(1)(2011).


[3] R.Wellington Davis, A.G.Robiette, and M.C.L.Gerry, J.Mol. Spectrosc. 81,93(1980).

[4] J.Demaison, M.Herman, and J.Liévin, J.Chem.Phys. 126,164305(2007).

 








 








Benzoic Acid H2CO HOCl CF3COOH

 








 








Table of Contents




Molecules/Deuterium




 








 













HCOOD.html






Last Modified 11 Dec 2010