Sciencemadness Discussion Board

Quick Questions Thread: No Easy Answers Edition

pepe - 21-8-2016 at 05:15

I am making this thread for my own edification but I am sure there are many that will benefit from something of this format. Basically this is a thread for questions and answers. Specifically we are seeking answers that can guide a seeker towards further research and understanding. Short questions are the focus and as you can see the sublabel is No Easy Answers which indicates that the answer may be more complex than the understanding of the person who posed the question.

To start off, in reading papers and texts I hear about spectroscopy and how various bands indicate the presence of various substances. my question comes from a very simple understanding of the spectroscopic process. Basically I am wondering if the bands refered to in spectroscopic readings are essentially atomic shadows. Is this a correct or semi correct understanding of the process or is there something I am missing?

https://en.wikipedia.org/wiki/Spectroscopy

Sulaiman - 21-8-2016 at 06:01


Crowfjord - 21-8-2016 at 06:55


Quote:

Basically I am wondering if the bands refered to in spectroscopic readings are essentially atomic shadows. Is this a correct or semi correct understanding of the process or is there something I am missing?


Depends on how you look at it, kind of. In my opinion, that isn't really how it works. A "band," sometimes also called as a "line" refers to a specific piece of the electromagnetic spectrum (wavelengths), where a substance either emits or absorbs. The type of spectroscopy determines whether you are looking at absorption or emission. Also, in many cases in spectroscopy, one tends to find peaks rather than lines or bands, due to Doppler effect and other phenomenon.

Fun facts: the type/energy level/area of the the electromagnetic spectrum determines what part of the atom or molecule's motion you're looking at. X-rays, UV, and visual radiation interact with the electron shells and energy levels. Infrared interacts with molecular bonds, causing resonant bonds to stretch or bend. Microwaves resonate with molecules' rotation (domestic microwaves are tuned to water's rotational frequency, and make the water molecules spin). Radio waves (as in NMR) interact with the magnetic field created by the spin of atomic nuclei, IIRC.

Spectroscopy is a broad, fascinating field. It's probably easiest to digest by researching one type at a time.

Bert - 21-8-2016 at 13:51

Oh yeah. Sticky?

moominjuice - 21-8-2016 at 15:19

Crowfjord; your description of spectroscopy was an elegant answer to a probing question from an inquiring mind. that is what good teaching is about, kudos :)