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 P25+ were proposed and full geometry optimizations were carried out with molecular mechanics, semi-empirical PM3 and density functional calculations. Then four models of P33+ were built based on the most stable P25+ and P8 isomers. Other cationic phosphorus clusters up to P89+ were also constructed. In these clusters, cuneane P8 polymerizes to a long tubular shape with one extra phosphorus atom located at the end.