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Elements that react with crystalline

  1. Aug 5, 2006 #1
    What element will react with crystalline causing it to lose it's organized pattern.
     
    Last edited: Aug 5, 2006
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  3. Aug 5, 2006 #2

    Gokul43201

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    There are hundreds of reactions involving crystals that result in loss of crystallinity. A common example is oxidation.
     
  4. Aug 5, 2006 #3
    Or if its a soluble crystal, a solvent like water.
     
  5. Aug 5, 2006 #4
    Almost all chemical processes will, as long as the product itself is not crystalline.
     
  6. Aug 6, 2006 #5

    Gokul43201

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    That was my first thought, but I wasn't sure how rigorous the OP was by the use of the term 'element'.
     
  7. Aug 6, 2006 #6
    Yeah, i dont think it even classes as a "reaction", to a chemist. Solvation that is. Where reaction implies a chemical reaction.

    I dont know much about liquid crystals, but they could also be an exception to that rule...intresting one too.
     
  8. Aug 7, 2006 #7

    NoTime

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    Liquid crystal is a long polar molecule (chiral too I think).
    AFAIK it is not any sort of crystal in the chemical sense.
    However, when in an electric field the heads and tails line up and form a periodic array. A sort of quasicrystal that polarizes light. Without the electric field they just asume a random orientation.
     
  9. Aug 8, 2006 #8
    I see, by quasi-crystal do you mean that the liquid develops regions of crystaline structure and some where it is still amorphous? Or that its only an induced crystallinity and not a natural one?

    These are similar to magnetic domains in ferromagnets no?
     
  10. Aug 8, 2006 #9

    NoTime

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    The nature of the beast is such that you will have molecules that don't cooperate. So you will have some residual amorphous areas.

    Primarily I just mean that, with an electric field, the liquid crystal molecules form a periodic array. Much the same way that an ordinary crystal is a periodic array of molecules or atoms. Unlike the ordinary crystal there are no chemical bonds being formed or broken as the electric field is applied. Induced crystallinity.

    I suppose there is some anology here.
    I don't think I would go to far with it though.
     
  11. Aug 8, 2006 #10
    Right you are, thanks.
     
  12. Aug 12, 2006 #11

    Gokul43201

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    Not true.

    In the complete absense of applied external fields, you can have both long-range anisotropy as well as long-range positional ordering. It only takes an electric field to make a macroscopic single-crystal.

    This is loosely analogous to the magnetization of a ferromagnet.
     
    Last edited: Aug 12, 2006
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