Why can some waves pass through materials but others can't

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Hello,

Why can some waves pass through materials but others can't. Why can visible light go through glass but infrared can't? I know it has to do with transmission but what is the fundamental processes? In as simple terms as possible? If anyone has any websites of books that might help please let me know.

Thank you for your help.
 
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Why do you think IR can't go through glass?
 
I saw a picture of a hand behind a sheet of glass in IR. But I guess the reason why it can't see it is because the heat isn't transferred to the air?
 
Are you near an incandescent light bulb? Turn it on and put your hand near it. Can you feel the heat?
 
Well in that case when I put my hand under a sheet of glass can I not see it in the IR?
 
i. is this HW question?
ii. I don't believe this is upper undergraduate level question.

You know that atoms of different kinds have different spectra, i.e the absorbtion lines are different for each element. The same holds for solids. Different solids absorbs Em rad at different wave lenghts. And this has to do with the so called band structure of the solid.

http://hyperphysics.phy-astr.gsu.edu/Hbase/solids/band.html

http://en.wikipedia.org/wiki/Band_structure

So depending on what atoms the solid are made of etc, different band structures arieses. You can think of these bands as the "orbitals" of the electrons in an atom. The bands tell you what electron can have.
 
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