History of Allotropy

	Revision 7 . . October 2, 2001 10:47 am by Stokerm [Clarified the relation with polymorphism and phase changes]
	Revision 6 . . September 22, 2001 12:44 pm by Simon J Kissane

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Changed: 10c10,12

Allotropy is not to be confused with the existence of multiple physical states, such as with water, which can exist as a gas (steam), a liquid (water), or a solid (ice). These phases of water are not allotropes. Allotropy specifically refers to the different physical forms a pure element can be found in.

Allotropy specifically refers to the chemical bond structure between atoms and should not be confused with the existence of multiple physical states, such as with water, which can exist as a gas (steam), a liquid (water), or a solid (ice). These phases of water are not allotropes, since they are caused by changes in the physical bonding between water molecules, rather than changes in the chemical bonding of the water molecules themselves. The word allotropy is usually restricted to the case of pure elements and is a special case of Polymorphism.