Homework 8B - IR and Raman Calculations Key
- Page ID
- 419396
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your numbers may differ...
| Molecule | IR frequency (frequencies) of vibrations (cm−1) | Raman frequency (frequencies) of vibrations (cm−1 ) |
| HF | 3791 | 3835 |
| HCl | 2725 | 2766 |
| HBr | 2501 | 2502 |
| HI | 2244 | 2244 |
Submit the above table filled out for the frequency of each molecule (do not copy from others)
- Plot up the IR frequency vs molecule size
- Compare the trend.
Frequency decreases as molecular size increases.
- Provide the IR plot presented in the calculation
There should be four of these. Here is an example:
- Provide an Ansatz: Why don't these spectra look like the vibrations that we saw in class?
Because the plots shown in class were gas phase or complex extended molecular systems that weren't these molecules.