We investigate ionic fragmentation of ${\mathrm{CO}}_2{}^{n+}$ ($2\le n\le 4$) produced in collisions with ${\mathrm{Ar}}^{q+}$ ($4\le q\le 16$) projectiles at a collision velocity of $\sim 0.3$ a.u., where electron capture is the dominant ionization mechanism. We report kinetic-energy-release distributions (KERDs) for the observed ionic fragmentation channels for the cases where the charge state of the projectile is reduced by $\mathrm{\Delta }q=1,2$ postcollision. For most projectiles, the KERD for $\mathrm{\Delta }q=2$ is observed to be broader than that for $\mathrm{\Delta }q=1$. The difference generally diminishes with increasing projectile charge. Two deviations are seen in the fragmentation of ${\mathrm{CO}}_2{}^{3+}$, one for ${\mathrm{Ar}}^{4+}$ impact in the high-kinetic-energy-release (high-KER) region and the other for ${\mathrm{Ar}}^{6+}$ impact in the low-KER region. The calculated reaction windows for multielectron capture within the framework of the extended classical over-the-barrier model indicate that while ionization of the target occurs via multielectron capture, the scattered projectile can subsequently undergo multifold autoionization. The observed correlation between the KERDs and the postcollision charge state of the projectile demonstrates a dependence between the excitation of the target and that of the scattered projectile.

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• Atomic & molecular collisions
• Charge-transfer collisions
• Molecular dissociation