Sign in to follow this  
foolishone

Molecular vs. Atomic Absorption Spectroscopy

Recommended Posts

foolishone    10

Does anyone know the difference between molecular absorption spectroscopy and atomic absorption spectroscopy? I know AAS destroys the sample, but I need to know another diffference? I tried searching but can't really find anything about MAS. Is there another name for MAS?

 

Thanks,

 

fo

Share this post


Link to post
Share on other sites
Dak    123

afaik, MAS is usually reffered to by the type of wavelength it's adsorbing, eg infra-red adsorption spectroscopy, UV-AS, or just electromagnetic adsorption spectroscopy, so you might want to search for terms such as those...

 

i think AAS measures the adsorption of the constituent atoms across a region of the EM spectrum, whilst MAS measures the adsorption of the molecule across a region of the EM spectrum.

 

I dont think AAS can identify substances, unless they are elements... i know it's used to identify heavy metals, but you can't, say, ID cannabis using AAS (tho i might be wrong)

Share this post


Link to post
Share on other sites
swansont    6252

Just to note, adsorption and absorption are two distinct processes.

Share this post


Link to post
Share on other sites
swansont    6252
I know AAS destroys the sample

 

I assume you mean that in order to use AAS on a sample, you have to atomize it; simply absorbing a photon isn't going to do anything to destroy the atom itself.

 

AAS is only going to involve electronic transitions, as there are no vibrational or rotational states to interrogate. It can tell you the constituent atoms but not how they were originally arranged.

Share this post


Link to post
Share on other sites
jdurg    31
I assume you mean that in order to use AAS on a sample, you have to atomize it; simply absorbing a photon isn't going to do anything to destroy the atom itself.

 

AAS is only going to involve electronic transitions, as there are no vibrational or rotational states to interrogate. It can tell you the constituent atoms but not how they were originally arranged.

 

Exactly. MAS will tell you that Carbon atom 1 was bound to oxygen atom 2, while AAS will only tell you that you have two oxygen atoms and one carbon atom but not how they were arranged.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

Sign in to follow this