An illustration of the crystal structure of ruthenium trichloride showing the simple honeycomb lattice of ruthenium ions and chlorine ions. The twisted octahedra formed by chlorine around the electron spin of each ruthenium atom are mirror images of each other. This twist is key to the compound's unusual behavior, which is evidence that it may contain an example of a quantum spin liquid. Credit: Courtesy of Arkady Shekhter/ National High Magnetic Field Laboratory