Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Energy Bands and Molecular Orbitals

  1. Sep 7, 2013 #1
    Hello, a newbie here. I need to understand the relationship between MO and Energy Bands.

    Although i have searched and researched about this topic in Google, but i am yet to understand this part clearly.

    It is said that Energy Bands occur as the number of MO increase due to the various atoms that are interlinked in a crystal structure.

    But i can't help but wonder.
    While K has its σ state fully filled and its σ* state empty, and yet behaves as a conductor
    But Si has ∏px and ∏py states partially filled which means when bands form, Si should have some bands which are partially filled and hence should be good conductors while Na should behave more of a semiconductor way... but it is just the opposite. Why?

    Attached Files:

    • Na.jpg
      File size:
      27.8 KB
    • si.jpg
      File size:
      29.7 KB
  2. jcsd
  3. Sep 7, 2013 #2


    User Avatar
    Science Advisor

    The diagram you show seems to be for diatomic molecules while the band structure refers to infinitely large crystals. Why do you think the two are comparable?
  4. Sep 8, 2013 #3
    Then what should i do to get a clearer picture of the MO and Energy Band conduction??
  5. Sep 8, 2013 #4


    User Avatar
    Science Advisor

Share this great discussion with others via Reddit, Google+, Twitter, or Facebook