#allotropy

• Allotropic — Relating to simple substances or chemical elements: presenting allotropy; capable of manifesting or crystallizing in two or more distinct external shapes or molecular and crystalline structures, possessing different physical properties, although the raw elemental chemical composition remains identical (for instance, diamond and graphite as allotropic forms of carbon).
• Allotropy — A property or structural phenomenon whereby a single chemical element, in its pure state (simple substance), can exist in two or more distinct molecular forms or crystalline structures, possessing completely different physical and often chemical properties (for instance, carbon existing as diamond, graphite, graphene, or fullerenes). The term applies strictly to elements, being the equivalent of polymorphism in mineralogy.
• Allotropism — A state, property, or structural phenomenon consisting of the capacity of a pure chemical element to exist under several distinct molecular forms or crystalline lattices (allotropy); the set of spatial geometric modifications that the atoms of the same simple substance can adopt, generating substances with totally different physical and mechanical properties, although the raw elemental composition remains identical.