Observation of doubly charged lead clusters below the critical size limit for Coulomb explosion of sphere configurations

Doubly charged lead clusters Pb₇²⁺, Pb₉²⁺, Pb₁₁²⁺ and Pb₁₃²⁺, far below the critical size for Coulomb explosion of par ticles with sphere like configurations (Pb₃₀) have been detected in time of flight mass spectra. Their existence can be explained by chain-like clusters.