Energy bands, or amount of electrons in shells that effects absortion in absortion, a

Jan 2016
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Would every solid object be transparent invisible if the electron never got exited fr

Would every solid object be transparent invisible if the electron never got exited from the ground state, or shell level 1.?
If it were possible to stop a electrons from getting excited in atoms, from all wavelengths of light, in a four inch cubed block of SOLID carbon, would the the SOLID carbon either be completely transparent, or invisible,
or would it be something else.
Thank you for your help, anything helps even a few words.

Note from the Mod:

I have merged five threads into one so that's why it looks so odd.

-Dan
 
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Jan 2016
45
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Do all electrons in all solid elements need 10 eV to get to the next shell

Do all electrons in all solid elements need 10 eV to get to the next shell orbit level.?
Is it different in glass though, than for a solid block of four inch carbon.
But why are energy levels different in electrons, so 10 eV is not the same for every electron, to move to shell 2 from the ground state, is this correct.
I am still learning about energy bands.
Thank you for your help.
 
Jan 2016
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nd , emissions spectrum.
My name is Nicholas Lee, and I am studying neuroscience, and I am trying to find a way to find better ways in neuroimaging, and microscopy to see the brain better, to find better cure for Parkinson's disease, and Alzheimer's, and epilepsy If you have a four inch cubic block of glass, and carbon, light passes through the glass no problem, but the carbon will absorb some red, yellow, green, and blue light, but if you look at the carbon absorption for light, not all blue, green, yellow, and red light get absorbed by carbon, like in the diagram below.
Inline image 1
Some materials have larger band gaps than others, glass is one of those materials, which means its electrons require much more energy before they can skip from one energy band to another, and back again.
glass cannot absorb high wavelengths of light, but the glass will absorb ultraviolet waves, which have a smaller wavelength.
So if the two four inch cubic block of glass, and carbon, are placed in a dark room with no light hitting the blocks at all, and you just shined the colors of light at the carbon, that did not excite the electrons to a higher shell energy level, what would happen.
Question 1. Does the light from the blue, green, yellow, and red pass through the carbon block, but I think you would just see the block of carbon just be black right, even though certain colors of light are passing through it, is this correct.
All light colors pass through the glass no problem, so for the carbon things are different, the amorphous material the glass is made from is not necessarily what is making the glass transparent, its the energy of the electrons in the glass that cannot get exited for the light, so the light gets transmitted through the block of glass.
So for the carbon, does its electrons either absorb more energy, or because it has 2 electrons in shell 1, and 4 electrons in shell two, silicone which is mostly what glass is made from has two electrons in shell 1,and 8 in shell 2, and 4 in shell 3.
So it cannot be the amount of electrons I think just the energy of electrons, but can you explain why the energy levels are different for some electrons.
Here are a list of some ways to effect electron:
1. Cold temperature, can this effect the way electron absorb photons of light.
2. Certain wavelengths of EM waves
3. Amorphous material.
4. energy of electrons.
Do you know of any other ways the electron can not get excited.
Thank you for your help, anything helps, even a few words.

Best regards,

Nicholas Lee.
 
Jan 2016
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Is the valence band, in the atom, the amount of electrons a atom has.

and, for the conduction band is where electron have left the shell orbitals in the atom.
Is this correct.
Thank you for your help, anything helps even a few words.
 
Jan 2016
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why would the valence, band, and conduction band have anything to do with absortion,

and emission, of photons of light, from the electron.
Thank you for your help.
 

topsquark

Forum Staff
Apr 2008
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635
On the dance floor, baby!
Merging all of these seemed to be the best solution since they are all more or less the same topic.

There is a whole course worth of material on band states in solids and I don't know how much background you have. The basic idea is that where atoms have electron "shells" molecules also have a version. When you have many molecules in a material the energy levels tend to blend and form what is called a "band." But it works the same way as with single atoms: When you fire a photon at the material, if there is an available energy state in the band the photon can excite the electron into the higher state. And the opposite also holds: An excited electron can drop down a level into a vacancy in the band.

I think the answer to many of your questions is explained above. The only one I can think of that hasn't quite been addressed is the transparency issue. An object will be transparent to a particular wavelength of light if the frequency of the light does not match the energy required to promote an electron to an excited state. (If the frequency did match the energy then the light would scatter and you wouldn't be able to pass through the material.) But it depends on the frequency of the light. For example, most materials are transparent to low frequency light...that's how we can use heat sensors to "see" through walls.

Let us know what more information you might need.

-Dan
 
Apr 2015
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250
Somerset, England
Electron promotion is not the only mechanism for the absorbtion of EM radiation by matter.

All matter is made of molecules. Only a small percentage of these molecules are single atoms, most are combinations of two or more atoms.

Even pure elements in the solid state are effectively giant molecules, not isolated single atoms.

The point of this is that the energy levels change as soon as an atom enters into combination with others to become part of a molecule.

The second point is that the spatial arrangement of atoms allows many sorts of vibrational modes of accepting radiation energy, particularly the longer sub visible light wavelengths.
 
Jan 2016
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Great, thanks for your help.

I still am studying about energy bands, but its complicated.
But if I think of it in this way, it is easier for me to understand.
So in glass, and solid elements, electrons have different energy levels.
Hydrogen gas needs 10 eV to move from the ground state to the shell level 2
So its going to take some electrons, in SOME elements to have more eV from light to move to a higher shell level.
Imagine 2 cubic 4 inch blocks if glass, and solid carbon.
Glass is made from 75% Silicone, Sodium, and Calcium.
Silicone has 14 electrons, 2 in the ground state, 8 shell 2, and 4 in shell 3.
Sodium has 11 electrons, 2 in the ground state, 8 shell 2, and 1 in shell 3.
Amorphous materials (noncrystaline) does not really effect the way light transmissions through a solid object, its the energy of electrons.
So can it be explained in science why electrons in glass, which are no different to the electrons in the solid carbon, do not absorb light, but the solid carbon block is absorbing, and emissioning light do.
If it can be explained, and its not a mystery, does it have something ro do with the spin of electrons, and the pauli exclusion principle.
Or the maybe the Silicone electrons in shell 2, and 3 need more eV to move to shell 4.
Is this why glass is transparent.
So glass being transparent, compared to the SOLID carbon block, is this the difference why, or am I wrong in this description.
Is it a mystery to science, physicists why electrons have different energy levels, or can it be explained.
Thank you for your help, anything helps even a few words.

Electron promotion is not the only mechanism for the absorbtion of EM radiation by matter.

All matter is made of molecules. Only a small percentage of these molecules are single atoms, most are combinations of two or more atoms.

Even pure elements in the solid state are effectively giant molecules, not isolated single atoms.

The point of this is that the energy levels change as soon as an atom enters into combination with others to become part of a molecule.

The second point is that the spatial arrangement of atoms allows many sorts of vibrational modes of accepting radiation energy, particularly the longer sub visible light wavelengths.