Yo-yo crystals are a new, rare kind of chiral porous material

Crystals resembling yo-yos are a new type of chiral, porous material. The crystals are formed from two concave discs attached to a central axle. From the side, the discs look like flowers with clearly defined petals. These flowers have a slight spiralling arrangement, meaning that the yo-yos have a chiral structure. Despite their complex shape, these are single crystals –confirmed by x-ray crystallography.