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Strange Attractors; May 1997; Scientific American Magazine; by Nemecek; 1 Page(s) Wave a magnet over a cup filled with iron filings, and it is hardly surprising to see them stand on end. It would be quite something else if passing a magnet over a cup of coffee could suddenly pull all the caffeine to the surface. Or if an old blueprint could stick to the refrigerator all by itself. Admittedly, these wonders are pretty farfetched, but chemists have recently rearranged the same organic constituents that make up caffeine and blueprint dye to produce two new kinds of magnets that are lighter, more flexible and easier to make than the common metal variety. Nonmetallic magnets work because magnetism is not a property of metals per se but of the electrons in them. Electrons have a property called spin that makes them behave like tiny magnets, each with north and south poles. When the spins on many adjacent electrons all point in the same direction, the overall effect produces the familiar poles of any magnet. Certain metals are easy to magnetize because they have an abundance of electrons just waiting to line up in magnetic order. But a number of nonmetallic substances have electrons to play with as well.
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