Cube-Shaped Carbon Molecules Don't Stack Up
Next time you pass by a bin full of oranges at the supermarket, consider how they're stacked. This arrangement of tightly packed spheres is often repeated when substances known as molecular solids (fullerenes being one example) are heated to a point where the individu
al molecules in the solid tumble rapidly about their centers, thereby looking like spheres. Such an arrangement was expected of the remarkable molecular solid known as cubane. First synthesized in 1964, cubane is a cube-shaped molecule with a carbon and hydrogen atom at each corner. The military has been studying cubane derivatives since they show potential as incredibly powerful explosives. Other cubane derivatives show potential for treating AIDS, cancer and Parkinson's disease.
al molecules in the solid tumble rapidly about their centers, thereby looking like spheres. Such an arrangement was expected of the remarkable molecular solid known as cubane. First synthesized in 1964, cubane is a cube-shaped molecule with a carbon and hydrogen atom at each corner. The military has been studying cubane derivatives since they show potential as incredibly powerful explosives. Other cubane derivatives show potential for treating AIDS, cancer and Parkinson's disease.Scientists at the National Institute of Standards and Technology's Center for Neutron Research recently di
scovered that at high temperatures, cubane molecules do not conform to the expected lattice configuration. Instead, because of the cubic geometry, the molecules organize into a rhombohedral grid (imagine a box squashed along one diagonal axis). NIST scientists measured cubane's unusual properties using neutrons and X-rays in experiments made more difficult by its tendency to convert quickly from a solid to a gas. These studies have provided scientists with a model that correctly predicts the observed structure, an important first step in developing the technological applications of other cubane-based compounds.
scovered that at high temperatures, cubane molecules do not conform to the expected lattice configuration. Instead, because of the cubic geometry, the molecules organize into a rhombohedral grid (imagine a box squashed along one diagonal axis). NIST scientists measured cubane's unusual properties using neutrons and X-rays in experiments made more difficult by its tendency to convert quickly from a solid to a gas. These studies have provided scientists with a model that correctly predicts the observed structure, an important first step in developing the technological applications of other cubane-based compounds.National Institute of Standards and Technology
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