Diamond stands up to a squeeze. Surprisingly, the material’s structure persists even when compressed to 2 trillion pascals, more than five times the pressure in Earth’s core, scientists report January 27 in Nature.
The study suggests that diamond is metastable at high pressures: It retains its structure despite the fact that other, more stable structures are expected to dominate under such conditions. Studying diamond’s quirks at extreme pressures could help reveal the inner workings of carbon-rich exoplanets (SN: 7/16/14).
Diamond is one of several varieties of carbon, each composed of a different arrangement of atoms. At everyday pressures on Earth’s surface, carbon’s most stable state is graphite. But given a forceful squeeze, diamond wins out. That’s why diamonds form after carbon takes a plunge inside Earth.
But at higher pressures than those found inside Earth,…