Frank-Kasper phases (soft matter)
Frank–Kasper phases (soft matter) are a class of ordered mesophases that adopt the tetrahedrally close-packed (TCP) symmetries originally discovered in intermetallic alloys. These structures have been observed in a variety of self-assembling soft matter systems, including liquid crystals, dendrimers, surfactants, and block copolymers.
Source: Wikipedia — Frank-Kasper phases (soft matter) (CC BY-SA 4.0)