The prediction of the isomers for phosphorus clusters P-5(+), P-5(+), and P-5

In the study of cationic phosphorus clusters produced in direct laser vaporization, it has been observed that P 5 + and P 5 - show the higher intensity in the mass spectrum. We acquired nine P 5 +, P 5 - and P 5 isomers with molecular graphics and then carried out the optimizations with molecular mechanics, PM3 semi empirical and ADF density functional calculations. In these isomers, the phosphorus atoms could be in two fold, three fold, four fold. According to bonding energies, the most stable P 5 + has the square pyramidal structure. The planar pentagon configuration of P 5 - has the lowest bonding energy. P 5 derived from the most stable P 4 by adding a twofold phosphorus atom has the most stable structure.