Helium’s inertness defied by high-pressure compound
Crushing elements together with diamonds creates a rare mash-up
HELIUM COMPOUND Scientists created a chemical compound of helium and sodium by squeezing the elements to extremely high pressures. Helium atoms (green cubes) are arranged in a 3-D checkerboard structure, each surrounded by eight sodium atoms (purple). Electron pairs (red) sit in the spaces between helium atoms.
Courtesy of A.R. Oganov