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Bizarre Properties of Glass Allow Creation of "Metallic Glass"
VindictivePantz writes to mention that scientists have discovered some bizarre properties of glass and are already applying that knowledge to create what is being called "metallic glass." "The breakthrough involved solving the decades-old problem of just what glass is. It has been known that that despite its solid appearance, glass and gels are actually in a 'jammed' state of matter — somewhere between liquid and solid — that moves very slowly. Like cars in a traffic jam, atoms in a glass are in something like suspended animation, unable to reach their destination because the route is blocked by their neighbors. So even though glass is a hard substance, it never quite becomes a proper solid, according to chemists and materials scientists."
One of the interesting aspects of this article is how it highlights the usual thermodynamic balance between entropy and free energy. States of matter in the equilibrium phase attempt to simultaneously maximize entropy, a measure of the statistical likelihood of a given state, and minimize the amount of energy "stored" in the given arrangement of molecules.
The most favorable condition is often a compromise between maximum entropy and minimum energy as highly ordered states, such as tetrahedral or other crystalline arrangements, often act to reduce the amount of stored energy due to minimized interatomic and/or intermolecular interactions and related factors. Pure crystals of substances will often form because the energetic "advantage" of the highly ordered crystalline state is often great enough to overcome entropic barriers.
The model that the researchers propose is interesting because the crystalline state itself introduces a degree of energetic disadvantage due to what is described as "cramming" of the individual crystalline unit cells. I wonder what models they used to form their hypothesis that the glass would eventually form a perfectly crystalline state.
Bingo. If glass flowed at any rate the glass vases found in Egyptian tombs would have been puddles. I can't believe this stuff still gets repeated.
"Technology.....the knack of so arranging the world that we don't have to experience it." Max Firsch
You're probably thinking of synthetic sapphire (which is aluminum oxide).