Phosphaethyne polymers are analogues of cis-polyacetylene and graphane

Spontaneous and rapid polymerization of phosphaethyne was previously observed, however the crystal structure and electronic properties of the polymer have not been studied in detail. In the present work, we investigated the stability and electronic structure of the polymers based on phosphaethyne, which were studied using density functional methods and compared with those of the polymers of acetylene (cis-polyacetylene and graphane) and phosphorus (black phosphorus allotrope). Similar to the reference compounds, the graphane-like layer structure of poly-phosphaethyne is considerably more thermodynamically stable than the oligomers and has no unsaturated chemical bonds; hence it can be synthesized. This also opens the way to chemically modify and fine-tune the properties of graphane by synthetically incorporating poly-phosphaethyne units in the layer structure. We would propose that when using appropriate reaction conditions, graphane-like structures can be prepared by polymerization of phosphaethyne.