Is it possible to have a shadow effect within a crystal latice at a atomic level ? ie can one atom be shielded from the effects of photons by a intervening atom.

Probably not. When doing x-ray crystallography, one rotates the crystal bit by bit over more than 180[math]^{o}[/math]. If an atom was "hiding" behind another, it should show up at some point when illuminated from a different angle.

Probably not. When doing x-ray crystallography, one rotates the crystal bit by bit over more than 180[math]^{o}[/math]. If an atom was "hiding" behind another, it should show up at some point when illuminated from a different angle.

 

my thoughts exactly

Probably not. When doing x-ray crystallography, one rotates the crystal bit by bit over more than 180[math]^{o}[/math]. If an atom was "hiding" behind another, it should show up at some point when illuminated from a different angle.

 

You said probably. Can you think of some hypothetical situations where this might occur? In an extremely large molecule maybe?

 

Like maitotoxin?

 

or a water molecule structure?

You have Beer's law, which says that macroscopically the intensity drops off exponentially. Atoms near the surface are more likely to interact.

You have Beer's law, which says that macroscopically the intensity drops off exponentially. Atoms near the surface are more likely to interact.

 

What?

[math]I = I_0 e^{-\alpha x}[/math]

 

Light gets absorbed, and this is more likely at the surface of a material. Interior atoms are shielded.

[math]I = I_0 e^{-\alpha x}[/math]

 

Light gets absorbed, and this is more likely at the surface of a material. Interior atoms are shielded.

 

So, pretty much, the closer to the interior you are as an atom, the less light that can possibly reach the surface of the atom. This equation is just explaining mathmatically why you get less light if you're further away, right?

So, pretty much, the closer to the interior you are as an atom, the less light that can possibly reach the surface of the atom. This equation is just explaining mathmatically why you get less light if you're further away, right?

 

The equation is for a bulk material, not a single atom. If you shine light on a material, the amount that penetrates falls off as an exponential.

Edited April 21, 200916 yr by swansont
fix typo

The equation is for a bulk material, not a single atom. If you shine light on a material, the amount that penetrates falls of as an exponential.

 

So its an exponetial decay equation? I'm just learning that in Algebra II

So its an exponetial decay equation? I'm just learning that in Algebra II

 

That's right.