I, jw4116, love MO's
BH3
Item Value Threshold Converged? Maximum Force 0.000890 0.000450 NO RMS Force 0.000583 0.000300 NO Maximum Displacement 0.003553 0.001800 NO RMS Displacement 0.002326 0.001200 NO
Frequency analysis log file JUSTIN WILSON BH3 SYM FREQ.LOG
Low frequencies --- 1161.0318 1207.5802 1207.5825
Frequency Optimized BH molecule |
| Mode | Symmetry | Frequency (± 100cm-1) | Intensity |
|---|---|---|---|
| 1 | A2 | 1161 | 93 |
| 2, 3 | x2 E' | 1207 | 14 |
| 4 | A1' | 2565 | 0 |
| 5, 6 | x2 E' | 2691 | 143 |
There are two reasons for the lack of 6 peaks in the IR spectrum, despite the number of modes calculated. The E' degenerate vibrational modes (2, 3 and 5, 6) absorb at the same frequency and hence cause the spectral peak to appear twice as large as the predicted intensity for 1 absorption. The other vibration (4) does not appears as it is IR inactive, symmetric and generates no dipole moment which is means it is unable to interact with the oscillating electric field.
