So funnily enough my PhD is in Raman spectroscopy and currently I'm in Jena at a conference on Raman Spectroscopy, so not too many brain cells were stretched when my first blog post is on Raman Spectorscopy.
If you ask anyone here at the conference explain Raman, they'll probably say something similar to me along the lines of
"Measurement of low energy excitations of molecular or crystalline systems, most commonly vibrational modes, by use of ineleastic scattering of light."
But that doesn't really help when explaining to someone who has no idea what any of that means, namely people with out a degree in physics. So how do I go about demystifying this and explaining the concept.
Well first off I'm going to say what Raman Spectroscopy does for us. As I'm sitting here I gather a real appreciation for the scale of the field, the technique is used widely in physics for looking at the structure of crystals, but also spans to biomedical research to characterise drugs and understand how the skin absorbs things.
So what is it?
Well Raman is a tool, a tool to look at the structure of things, everything essentially has a unique Raman fingerprint and using this technique we can identify the compositions and structure of a sample by understanding this finger print.
Let me elaborate on this thought, as I sit here tapping my finger on the wooden table I hear a sound, this is the result of my imparting energy to the table, energy transfers through the whole structure of the table and a sound is generated due to the vibrations, try it yourself, and you know the sounds, a solid 'thunk' if you heard it experience will tell you it's wood. Now the glass next to me, I tap that and the sound produced is much lighter, a ringing sound that lasts as the vibrations are dissipated through the glass. I'm sure you know this sound as well. In fact you can identify most things by the sound they make, and that is akin to Raman. Instead of hitting an object, we transfer energy using a laser, this produces vibrations and by looking at the 'spectra' we can identify the structure.
Uh-oh! Spectra....I've said something new, so now let's get physical.
After exciting our material with a laser and energy is transferred to the vibrations, the system then re emits the light, except it doesn't have the same energy, it can't, as some of it has been turned to vibrations. So it emits this light at a different energy to the incident energy.
If we count the photons of light emitted and compare them to the incident light energy then that difference must be the energy of the vibration.
There we go, Raman Spectroscopy in a nutshell.
So to review in a bit more physical way
When I get back to a computer I'll repost this with pictures and equations, but hope this helps.
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