Structure prediction of large cationic phosphorus clusters

Guided by the mass spectrum of cationic phosphorus clusters produced in direct laser vaporization, we optimized nine P₈ isomers with density functional calculations and chose the most stable cuneane P₈ as building units for larger clusters. Eight isomers of P⁺₂₅ were proposed and full geometry optimizations were carried out with molecular mechanics, semi-empirical PM3 and density functional calculations. Then four models of P⁺₃₃ were built based on the most stable P⁺₂₅ and P₈ isomers. Other cationic phosphorus clusters up to P⁺₈₉, were also constructed. In these clusters, cuneane P₈ polymerizes to a long tubular shape with one extra phosphorus atom located at the end.