I am looking to understand this at a molecular level. Or should I look to the atoms and electrons?
In: Chemistry
>I am looking to understand this at a molecular level. Or should I look to the atoms and electrons?
Yes. All of the above.
Every individual electron has a property called “spin”. Spin is tricky, but for our purposes it basically makes every electron behave like a tiny magnet.
But that’s not enough.
Most atoms have all their electrons paired up, with 2 in every orbital, every “free space” an electron can take. When 2 electrons share a spot, their spins point in opposite directions and their magnetic fields cancel out. So you need atoms with lots of unpaired electrons so that they can all point in the same direction and make the whole atom act like a magnet.
But that’s not enough.
Then, you need to make a solid chunk of those atoms, and they all need to line up in such a way that all of the individual atoms in a crystal of the material tend to point in the same direction.
But that’s not enough.
You need to align all of the different crystal’s magnetic fields to all point in the same direction.
But that’s not enough.
If the material gets too hot, the motion of the atoms shaking around will shuffle the directions their magnetic fields are pointing too strongly for them to line up. You need materials that can overcome this effect at room temperature.
Only then can you have a permanent magnet. As it turns out, the only pure elements that can do this are Iron, Nickel, and Cobalt. Certain compounds like the Neodymium/Iron/Boron ceramic used in Rare Earth Magnets also fit the criteria.
Latest Answers