One-Dimensional Phosphorus Nanostructures: from Nanorings to Nanohelices.

Phosphorus nanorings and nanohelices-speculated to exist over 20 years ago-have been systematically derived from one parent structure and studied with quantum chemical methods. The (P P ) nanorings have been recently synthetized inside carbon nanotube templates, and our comprehensive analysis of possible structural arrangements strongly supports the possibility to experimentally determine the closely related (P P ) nanohelices. The nanohelices possess very low stiffness, suggesting interesting mechanical properties with nano-spring-like behavior.