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I How thick does a material have to be to start to become opaq

  1. Jan 25, 2016 #1
    -que to light?

    Someone said a atom is transparent to light to me.
    but as a material get more thicker, either in single atoms, or a micron, electrons start to absorb light, and there is no more transparency
    How thick does a material have to be before there is no more transparency.
    Like the material acts as a wall to light.
    Now solid state physics can be VERY DIFFERENT than atomic physics.
    When atoms are joined together to form a solid, their behavior can be very different than when they are isolated. There are no more "discrete energy states" at the low-lying range, because these have been replaced by energy BANDS!.
    If I take carbon atoms, and arrange it in one way, I get graphite.
    But I change the arrangement in another way, I get diamond!
    Two completely different types of material, and with different optical properties.
    Yet, each one of them is made of carbon.
    Thank you for your help, anything helps,even a few words.
  2. jcsd
  3. Jan 25, 2016 #2


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    Gold need only be a couple of atoms thick to be opaque.
    Water needs to be many tens of metres thick to be opaque.
  4. Jan 25, 2016 #3
    Thank you
  5. Jan 28, 2016 #4
    Great thank you.
  6. Jan 28, 2016 #5


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    Are you aware that you plagiarized one of my posts?

    If you are CITING someone, either use the QUOTE function, or quote what you are copying in " ". Otherwise, this looks as if this was ALL written by you!

    And why are you starting a new thread, rather than asking this as a follow-up to the thread that had this passage that you copied? You have started numerous threads on almost the SAME topic.

    Last edited: Jan 28, 2016
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