Fig. 2: Sequential cluster dissociation processes forming \({{{{{{{{\rm{O}}}}}}}}}_{2}^{+}\).
From: The origin of enhanced \({{{{{{{{\rm{O}}}}}}}}}_{2}^{+}\) production from photoionized CO2 clusters
a Dalitz plot (guide for interpretation is provided in Supplementary Fig. 2) showing the momentum distribution between the fragments in the \({{{{{{{{\rm{O}}}}}}}}}_{2}^{+}/{{{{{{{{\rm{CO}}}}}}}}}_{2}^{+}\) channel for different mean cluster sizes (Nmean). In the centre, we schematically show the three-body dissociation of the mother cluster into \({{{{{{{{\rm{O}}}}}}}}}_{2}^{+}\), \({{{{{{{{\rm{CO}}}}}}}}}_{2}^{+}\) and the undetected residual cluster fragment. For smaller cluster sizes Nmean ~4, we observe a distribution labelled region A (in red, left-hand side of Dalitz plot), for larger cluster sizes a second distribution labelled region B (in blue) appears to the right. b The cluster-size dependence of the intensity ratio between region A and region B from the \({{{{{{{{\rm{O}}}}}}}}}_{2}^{+}/{{{{{{{{\rm{CO}}}}}}}}}_{2}^{+}\) channel. The error bars for the Nmean values are calculated as described in Harnes et al65. The geometry of the doubly-charged cluster evolves from a 2Y-structure for small clusters to a polyhedral structure for cluster sizes above 11.
