3D crystal: A new carbon allotrope called diamondiyne is a porous material with the basic shape of a tetrahedron. (Courtesy: Yizhou Yang)

Researchers in Sweden have synthesized a new allotrope of carbon which, like diamond, forms covalent bonds in 3D. Unlike in diamond, however, carbon atoms in the new “diamondiyne” material form these bonds at relatively low pressure, producing a more porous crystal with properties that are still under investigation.

Carbon is among the most versatile elements in the periodic table. Because it can bond with other elements in one, two or three dimensions, it is a building block for a wide range of structures with varying electronic properties.…