Mass Spectrometric Study of Clusters Produced by Laser Vaporization of Some Phosphates

The clusters generated by direct laser vaporization of KH₂PO₄ and Cu₃（PO₄）₂ samples are studied by a TPF mass spectrometer.It is found that mainly the K（KPO₃）_n⁺ cluster series is generated from KH₂PO₄ sample and it demonstrates obvious magic numbers,which are n=3,6,9,12,15.Shch magic numbers strongly suggest the structure of packed potassium metaphosphate trimers.Direct laser vaporization of Cu₃（PO₄）₂ sample produced Cu（CuPO₃）_n⁺ cluster series as well as other series with the same building block of （CuPO 3）.It is inferred that cupric phosphate cluster ions probably have chained structures.