Multiply Charged Clusters

Abstract

We review progress made in understanding Coulomb explosion of multiply charged atomic clusters. Their collision with highly charged atomic ions leads to clusters in charge states as high as z = 10 with little vibrational excess energy; these systems approach the Rayleigh limit. Phase transitions become evident at higher excess energies. Numerous studies have been devoted to C z+ 60 , like collisions with surfaces, multi-coincidence fragmentation analysis and gas-phase reactions. Stability and decay of highly charged micrometer-sized droplets and of metal di-and trianions have been monitored in ion traps. Excitation by femtosecond laser pulses allows to unravel properties of highly charged transient cluster ions. To cite this article: O. Echt et al., C. R. Physique 3 (2002) 353-364.  2002 Académie des sciences/Éditions scientifiques et médicales Elsevier SAS Agrégats multichargés Résumé Cet article présente une revue des progrès obtenus dans la compréhension de l'explosion coulombienne des agrégats atomiques multichargés. Leur collision avec des ions atomiques hautement chargés conduit à des agrégats d'état de charge aussi élevé que z = 10 et contenant un peu d'énergie vibrationelle en excès. Ces systèmes approchent la limite de Rayleigh. Des transitions de phase apparaissent de manière évidente pour des excès d'énergie plus élevés. De nombreuses études ont été consacrées aux C z+ 60 , concernant par exemple les collisions avec des surfaces, ou bien l'analyse en multicoincidence de la fragmentation, ou encore les réactions en phase gazeuse. La stabilité et la décroissance de micro-gouttes hautement chargées et d'agrégats métalliques deux et trois fois négativement chargés ont été examinées dans un piège à ions. L'excitation par lasers femtosecondes permet de différencier les propriétés de ces agrégats ionisés hautement chargés. Pour citer cet article : O. Echt et al., C. R. Physique 3 (2002) 353-364.  2002 Académie des sciences/Éditions scientifiques et médicales Elsevier SAS * Correspondence and reprints.

Unraveling the Metastability of Cn2+ (n = 2–4) Clusters

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