A nano-sized slice of pie

Researchers have unlocked the secret to one of the most useful nanostructures: the five-fold twin. Nanomaterials with this structure – the cross-section of which looks like a pie sliced into five symmetrical pieces – are used in medical research for imaging and tracking cancerous tumors and in electronics, where they are valued for their mechanical strength. The researchers discovered two different mechanisms for forming five-fold twinned nanostructures, both of which are shaped by the accumulation and elimination of strain toward an ideal shape that eliminates all strain.