**Scientists reveal twisting-untwisting-retwisting cycle of nanohelices**

Reversible nanohelix transformation is one of the most exquisite and important phenomena in nature. Nanomaterials rarely form helical crystals. Due to the irreversibility of the twisting forces studied so far, untwisting is more difficult than retwisting crystalline nanohelices. Therefore, many reversible twist transformations between two stable crystalline products are rare and require a sensitive energy balance. This reversible transformation of nanohelices has long been considered difficult to achieve.

https://phys.org/news/2023-09-scientists-reveal-twisting-untwisting-retwisting-nanohelices.html