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Ionisation by a magnetic field?

  1. Sep 28, 2011 #1
    Is it not possible that, given a powerful enough magnetic field, the binding energy of an electron in a stable, neutral atom could be overcome from the tearing of the negatively charged electrons in one direction, and of the positively charged nucleus in the other?

    I have searched online, and there doesn't seem to be a mention to this anywhere...

    If this were to be true, I imagine that it would have been used already to form otherwise unobtainable negative ions, and make brand new compounds. Such a revolution has obviously not happened, so what is the problem with my logic?

    If the problem is that it requires too strong a magnetic field to be produced by human technology, how could the theoretical power required be calculated.

    Cheers, Kael.
     
  2. jcsd
  3. Sep 28, 2011 #2
    Do you understand what a magnetic field is and how charged particles are affected by them?
     
  4. Sep 29, 2011 #3
    I was fair sure I did, but it has been a while since I dealt with them, and your question seems to imply I don't. I'll google them to refresh my memory.
     
  5. Sep 29, 2011 #4
    Took a look. Nothing seems to contradict the logic I found. Positive and negative particles are pulled in circles in opposing directions. In the case of an atom, It would simply be a fight between the pull of the field and and the binding energy of the electrons... wouldn't it?
     
  6. Sep 29, 2011 #5
    No. Electric fields pull electrons and nucleii apart, and you can field-ionize atoms this way with sufficiently strong electric fields. What this has to do with "otherwise unobtainable negative ions", I do not have the slightest clue, but magnetic fields are not electric fields - they can change atomic structure and affect emission and absorption spectra, but they do not by themselves ionize atoms.
     
  7. Nov 29, 2011 #6

    fluidistic

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    I'm a bit late here, but I think an enormously strong magnetic field could indeed ionize some atoms. The problem is that as far as I know the ones we obtain in the lab (see there: http://en.wikipedia.org/wiki/Orders_of_magnitude_(magnetic_field [Broken])) are too small or they seem to blow up material.
    I think we can use the formula [itex]\Delta E =m_l \mu _B B[/itex] (although I am not 100% sure, maybe this formula instead : [itex]\Delta E =(m_l+2m_s) \mu _B B[/itex]. Can someone tell me which one to use for a huge magnetic field?). For example we can take [itex]m_l=1[/itex].
    In any case I suggest you to read about the Paschen-Back effect.
     
    Last edited by a moderator: May 5, 2017
  8. Nov 29, 2011 #7
    I remember watching this episode about the manhatten project where they used magnets in isotope seperation to help purify uranium.

    http://en.m.wikipedia.org/wiki/Isotope_separation

    This required an large amount of energy. I think its safe to say your system would require quite a bit more.
     
  9. May 20, 2013 #8
    Hey guys, I was wondering if anyone could expound on this question, even though it's old, I wanted to add in to the question here on whether a magnetic field could be strong enough to propel the atoms into collision with some ferromagnetic element such as Iron.
     
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