Vibration Spectroscopy--Study Notes

Recently, I have been studying vibration spectroscopy, i.e. the vibration infrared and Raman spectroscopy, which indicates the vibration 'fingerprint'of molecules. This is a totally new topic to me, so I didn't know anything about it before, thus I started from zero. Now, I have finished the first step and understand the basics about it. My study notes to this topic can be found in the vibration spectroscopy notes.