Why silver atoms reflect light?

In summary, the reason silver atoms reflect light is due to the interaction between the light and the conduction electrons within the metal. This results in the emission of electromagnetic waves in all directions, as opposed to the Huygens's principle which explains refraction. When polished into a smooth surface, silver metal is highly reflective due to its high conductivity, which is necessary for efficient reflection. In comparison, iron has a lower conductivity and therefore is not as effective at reflecting light. Additionally, the structure and arrangement of atoms within a material also play a role in its reflective properties.
  • #1
why silver atoms reflect light? why they don't refract it, like the Huygens's principle says?
 
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  • #2
Well, you need to go quite deep to get the full understanding here.

In short, your answer would be "plasmons" :)The conduction electrons in the metal will start to vibrate longitudinally as a response to the incident EM-radiation (ie the electrons will move back and forth, as a reaction to the incident oscillating electrical field). It is this oscillation of conduction electrons that gives rise to the phase shifted reflected light of a conductor.

The plasma frequence is that frequence above which the electrons can no longer 'follow' the oscillating incident E-field. This kinda means that the E field is vibrating too fast and the electrons cannot respond anymore to that motion. If this happens, the E field (thus light as well) will no longer be reflected but it will pass through the medium.

Plasmons are the particles that are associated with the longitudinal waves of the conduction electrons in a metal that has been submitted to incident EM-radiation (just like photons are the particles associated to EM radiation).

Hope that helps,

regards
marlon
 
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  • #3
marlon said:
Well, you need to go quite deep to get the full understanding here.

In short, your answer would be "plasmons" :)


The conduction electrons in the metal will start to vibrate longitudinally as a response to the incident EM-radiation (ie the electrons will move back and forth, as a reaction to the incident oscillating electrical field). It is this oscillation of conduction electrons that gives rise to the phase shifted reflected light of a conductor.

The plasma frequence is that frequence above which the electrons can no longer 'follow' the oscillating incident E-field. This kinda means that the E field is vibrating too fast and the electrons cannot respond anymore to that motion. If this happens, the E field (thus light as well) will no longer be reflected but it will pass through the medium.

Plasmons are the particles (well quasi particles actually) that are associated with the longitudinal waves of the conduction electrons in a metal that has been submitted to incident EM-radiation.

Hope that helps,

regards
marlon

Isn't the property of reflection of the mirrors, is result of the silver atoms? Are the EM waves released from the atoms, are released in whole directions?
Thanks.
 
  • #4
Physicsissuef said:
Isn't the property of reflection of the mirrors, is result of the silver atoms? Are the EM waves released from the atoms, are released in whole directions?
Thanks.

What atoms are you talking about ? You don't need to consider atoms individually here. We are talking about metals for example : metals are many particle systems, many atoms interacting with each other. Such systems have different properties like conduction and valence bands which you will not find in the case of individual atoms !

Basically, metals reflect incident light because of the interaction between the light and the conduction electrons inside the conduction band ! That is what i am talking about.

marlon
 
  • #5
marlon said:
What atoms are you talking about ? You don't need to consider atoms individually here. We are talking about metals for example : metals are many particle systems, many atoms interacting with each other. Such systems have different properties like conduction and valence bands which you will not find in the case of individual atoms !

Basically, metals reflect incident light because of the interaction between the light and the conduction electrons inside the conduction band ! That is what i am talking about.

marlon
They absorb the energy, and re-emit it? Do they release the waves in whole directions, like in the Huygen's principle?
 
  • #6
Isolated silver atoms do not reflect light. Silver metal reflects light, and even then only when polished into a nice smooth surface sufficiently large.

I don't understand your intepretation of Huygen's principle to exclude reflection.
 
  • #7
Why does polishing a metal make it reflective? And I think the question remains, what in the silver metal plate exactly makes it a better reflective metal than, say iron? It is not a better conductor metal I think, so what is the major property of silver that makes it the best substance for mirrors?
 
  • #8
Yoni said:
And I think the question remains, what in the silver metal plate exactly makes it a better reflective metal than, say iron? It is not a better conductor metal I think,
You really should look things up first. Silver has the highest conductance of any metal, with more than 6 times the conductivity of iron. Nobody uses iron wiring in their house. It is illegal to do so in many places! We use copper instead. Copper has a conductivity close to that of silver but costs a lot less than silver.
 
  • #9
D H said:
You really should look things up first. Silver has the highest conductance of any metal, with more than 6 times the conductivity of iron. Nobody uses iron wiring in their house. It is illegal to do so in many places! We use copper instead. Copper has a conductivity close to that of silver but costs a lot less than silver.

What the conductivity has to do with reflection? Why the silver atoms reflect 99% of the light which interacts with them. Why glass 96% reflects, and 4% refracts light?
 

1. Why do silver atoms reflect light?

Silver atoms reflect light because of their unique atomic structure. The outermost electrons of silver atoms are loosely bound, allowing them to easily interact with incoming light waves. When light hits a silver atom, the electrons absorb the energy and then quickly release it, causing the light to reflect off the atom's surface.

2. How does the reflective property of silver atoms compare to other elements?

Silver is one of the most reflective elements, with an average reflectivity of 95%. This is due to its high atomic number and the arrangement of its electrons, which make it highly efficient at reflecting light. In comparison, other elements such as copper and gold have lower reflectivity values.

3. Is the reflectivity of silver atoms affected by their surroundings?

Yes, the reflectivity of silver atoms can be affected by their surroundings. When silver is in a pure, smooth form, it reflects light with very little absorption. However, when silver is exposed to impurities or is in a rough, oxidized state, its reflectivity can decrease.

4. Can silver atoms reflect all types of light?

Silver atoms have a broad range of reflectivity, meaning they can reflect light of all wavelengths. However, the amount of light reflected may vary depending on the wavelength and the properties of the silver surface.

5. How does the reflective property of silver atoms make them useful in everyday life?

The high reflectivity of silver atoms makes them useful in various everyday applications. Silver is commonly used in mirrors, solar panels, and reflective coatings for glass and other materials. It is also used in photography and technology, such as in CDs and DVDs, due to its reflective properties.

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