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Magnetic field of molecules

  1. Dec 12, 2013 #1
    Do molecules have intrinsic magnetic fields to them? Lets say you have a water molecule H20. Would the oxygen have a field due to the orientation of it's electrons, and possibly the hydrogens fields act to reduce that field? I'm just curious.
  2. jcsd
  3. Dec 12, 2013 #2
    It changes depending on the movement and placement of the charges as far as the magnetic fields are concerned. When looking at water we are seeing the 'average' behavior of the interactions of these fields of a large group of likely very dynamic molecules.
  4. Dec 12, 2013 #3
    Well lets say you look at one water molecule. Does it have a magnetic field or does the random interaction of electrons cancel all magnetism out?
  5. Dec 12, 2013 #4
    Once a magnetic field is generated from a moving charge it moves away at the speed of light as an EM wave so unless there is an exactly equal but opposite EM wave emanating at the same time then no.
  6. Dec 13, 2013 #5


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    There are molecules with a permanent magnetic moment. In most of them it is due to the spin of the electrons, e.g. in many transition metal compounds. There are a few were the orbital moment is responsible for part or all of the magnetic field like in nitrogen-monoxide or singulet oxygen.
  7. Dec 13, 2013 #6

    sort of, but better to understand the magnetic moments [field orientations] add as vectors;some examples here:


    Fundamental particles have intrinsic spin.....and an associated magnetic moment
    check out

    Last edited: Dec 13, 2013
  8. Dec 13, 2013 #7
    I was wondering when you guys were going to chime in.

    Annored, this the the quantum mechanical view of how these molecules behave and is currently the best and most accepted model for the behavior of such structures. What I presented is the classical description which is typically only used for macro systems.

    It's a wonderful part of science today and represents a split between two very different types of Physics as experiment shows it seems to 'change' when we zoom in for a closer look at atomic scales.
  9. Dec 13, 2013 #8
    you can also some find interesting material in Wikipedia under


    Note the first illustration, top right.....

    And as you may know, microwave heating relies on
    with a funny story here:


    I wonder how the candy melted before he did....
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