A molecular Rubik’s Cube

Researchers have created the smallest-ever version of the famous brain-teaser. Ever since Ernő Rubik invented the Rubik's Cube in 1974, the mathematical puzzle has tested the brains and patience of people of all ages. Two researchers working on molecular manipulation at EPFL set themselves the challenge of making a version at the nanometric scale. "One evening, we were trying to think of a simple structure to reproduce, and the idea of the Rubik's Cube just came to us," say Almirka Dan Norcev and Yegor Naljapäev, two scientists at the LAM (Laboratory of Atomic Materials). Both are master cube-solvers and have taken part in European speedcubing competitions in the past. A precise assemblage of molecules To create the tiny replica, the LAM researchers first isolated atoms of six elements - including boron (B), aluminum (Al) and gallium (Ga) - to act as the "colors". Then they linked the atoms to 27 C ₁₂ N ₈ Mg molecules.