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Chemistry / Re: Can magnetic fields move electrons to a higher energy shell?
« on: 16/06/2016 02:10:48 »
A static magnetic field can influence electrons somewhat, but the effect is very slight. Even with some of the most powerful magnets in the world, the effects can only be noticed in special cases. For instance, some molecules will adopt a slightly different electronic structure than would be preferred in the absence of an applied magnetic field.
no field with field applied
−− −− −↑− −↑−
−↑↓− −↑↓− −↑− −↑−
This will only effect electrons in the highest orbitals (levels), and only when the band gap is very small. The energy of the interaction of the electrons with the field must overcome the interaction of the electrons with each other and the energy of the band gap.
This is most commonly observable in molecular orbitals with substantial contribution from d and f orbitals (from transition metals or rare earth metals), where the energy levels are closely spaced, and spin-orbit coupling allows electrons to align more efficiently.
So while it is technically possible to effect the electronic structure of some select molecules and materials with a static field, one needs a very strong field to maybe have some fairly minor effects. Alternatively, one can use an alternating magnetic field, which will have a much greater influence over the electrons--but this is electromagnetic radiation (one cannot have an oscillating magnetic field without the associated oscillating electric field).
no field with field applied
−− −− −↑− −↑−
−↑↓− −↑↓− −↑− −↑−
This will only effect electrons in the highest orbitals (levels), and only when the band gap is very small. The energy of the interaction of the electrons with the field must overcome the interaction of the electrons with each other and the energy of the band gap.
This is most commonly observable in molecular orbitals with substantial contribution from d and f orbitals (from transition metals or rare earth metals), where the energy levels are closely spaced, and spin-orbit coupling allows electrons to align more efficiently.
So while it is technically possible to effect the electronic structure of some select molecules and materials with a static field, one needs a very strong field to maybe have some fairly minor effects. Alternatively, one can use an alternating magnetic field, which will have a much greater influence over the electrons--but this is electromagnetic radiation (one cannot have an oscillating magnetic field without the associated oscillating electric field).