Diamond and graphite have a new carbon cousin called diamondiyne, with a crystal structure confirmed so far only in microscopic patches.

A carbon structure proposed 35 years ago has finally taken shape in a thin film where two liquids meet. Using relatively inexpensive equipment, researchers at the University of Gothenburg have created diamondiyne for the first time, adding a new three-dimensional structure to the forms carbon can take.

Diamondiyne is a carbon allotrope, a form of the element distinguished by how its atoms are arranged. Diamond and graphite are familiar examples. To create diamondiyne, the researchers joined carbon atoms through triple bonds. The material crystallizes into a network of tetrahedra, shapes with four triangular faces, connected corner to corner in all three dimensions.