Multiphoton Stimulated Desorption: The Geometrical Structure of Neutral Sodium Chloride Clusters
It is shown that multiphoton induced fragmentation can serve as a tool for structural investigation of clusters. Sodium chloride clusters are generated by condensation in warm or cold helium gas. In mass spectra of warm clusters taken by multiphoton ionization magic numbers show up which are different from the anomalies reported so far, and which are independent from the photon energy. They are explained by electronic excitation of sodium halide admolecules desorbing before ionization and leaving rectangular neutral cluster cores. In contrast, cold clusters show the well-known magic numbers of ion cuboids if they dissociate after ionization.
KeywordsMagic Number Alkali Halide Cluster Core Neutral Cluster Sodium Halide
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- 3.R. Pflaum, K. Sattler, and E. Recknagel, Observation of a new set of anomalies in mass spectra of CsI cluster ions close to the ionization threshold, Phys. Rev.B33:1522 (1986)Google Scholar
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