We report a channel-resolved study of intense-field Coulomb explosion in the HCl dimer, induced by a linearly polarized 6-fs laser pulse and analyzed through an ensemble of ${\mathrm{H}}^{+}$ and ${\mathrm{Cl}}^{+}$ ion trajectories. Three primary fragmentation pathways emerge: a minor three-body channel alongside two four-body channels—one proceeding sequentially and one near simultaneously—involving the dissociation of both monomers. The principal finding is that pathway selection is strongly correlated with the extent of ionization during the laser pulse, which is in turn critically sensitive to the orientation of the dimer with respect to the laser polarization direction. Higher early-time ionization predisposes the system toward near-simultaneous four-body breakup, whereas lower ionization favors sequential and three-body fragmentation; for low-ionization cases, a fragment-resolved charge metric further differentiates three-body and sequential behavior. These charge-dependent trends consistently map onto experimentally accessible observables: the simultaneous mechanism dominates the high-energy tail of the kinetic energy release (KER) of the fragment ions and populates distinct regions of the emission-angle distributions, while sequential events concentrate at lower KER. Overall, early-time charge evolution provides a unifying explanation for channel branching and for the channel-resolved fragmentation signatures.

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• Atomic & molecular processes in external fields
• Molecular dissociation
• Single- and few-photon ionization & excitation
• Strong electromagnetic field effects
• Ultrafast phenomena