Force field analysis for point group C
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Number of atoms: 4
Your 
3N representation
can be reduced to
A1= + |
A2=- |
E1= |
E2= |
E3= |
E4= |
| 4 |
0 |
4 | 0 |
0 |
0 |
Substraction of translational and rotational contributions results in
| A1=+ |
A2=- |
E1= |
E2= |
E3= |
E4= |
| 3 |
0 |
2 | 0 |
0 |
0 |
Infrared and Raman activities (harmonic approximation)
| Method |
A1=+ |
A2=- |
E1= |
E2= |
E3= |
E4= |
| Infrared |
+ |
- |
+ |
- |
- |
- |
| Raman |
+ |
- |
+ |
+ |
- |
- |
No. 1 : Total number of force constants 
.
No. 2 : Total number of force constants k.
No. 3 : Total number of nonvanishing force constants k.
Symmetry properties of force field parameters
| Force field |
A1=+ |
A2=- |
E1= |
E2= |
E3= |
E4= |
| linear |
3 |
0 |
2 |
0 |
0 |
0 |
| quadratic |
9 |
1 |
6 |
3 |
0 |
0 |
| cubic |
19 |
3 |
18 |
9 |
4 |
0 |
| quartic |
39 |
9 |
38 |
26 |
12 |
5 |
| Number of independant internal coordinates |
3 |
Literature
- J.K.G. Watson, J. Mol. Spec. 41 229 (1972)
The Numbers of Structural Parameters and Potential Constants of Molecules
Last update November, 13th 2023 by A. Gelessus, Impressum, Datenschutzerklärung/DataPrivacyStatement
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