The ${\mathrm{He}}^{+}$ charge-state survival probability sets the absolute scale of quantitative low-energy ion scattering (LEIS), and a recent ${\mathrm{CaSiO}}_3$ study [J. Brötzner et al., Phys. Rev. B 113, 075405 (2026)] has shown that this probability depends on whether the backscattered trajectory involves one, two, or several collisions—suggesting that quantitative analysis ought to discriminate by collision history. How far this regime hierarchy generalizes is, however, an open question. This is addressed through scattering-regime-resolved binary collision approximation (BCA) simulations of ${\mathrm{He}}^{+}$ at 1–3 keV under grazing incidence $(\psi ={22}^{\circ })$ for four crystallographically distinct targets: $\alpha$-quartz ${\mathrm{SiO}}_2$, corundum $\alpha \text{−}{\mathrm{Al}}_2{\mathrm{O}}_3$, wurtzite GaN, and zincblende 3C-SiC. The calculations combine pair-specific Nordlund-Lehtola-Hobler potentials, position-dependent electronic stopping, Debye thermal vibrations, and a velocity-dependent Hagstrum kernel; statistically converged trajectory ensembles were accumulated for the high-statistics analysis. For $\alpha \text{−}{\mathrm{SiO}}_2$, GaN, and 3C-SiC, the standard ordering ${\langle P^{+}\rangle }_s>{\langle P^{+}\rangle }_d>{\langle P^{+}\rangle }_m$ is recovered, with single-to-multiple contrast $R_{s/m}\approx 1.5–2.2$. Corundum exhibits a qualitatively different behavior. When the backscattered ensemble is decomposed by the chemical identity of the final-collision atom, dual-scattering trajectories ending on the dominant Al sublattice show a charge survival below that of multiple-scattering ones at all five investigated energies. The sublattice-resolved inversion is highly significant—$19.7\sigma$ at 1 keV in the pooled three-seed ensemble, weakening monotonically to $3.7\sigma$ at 3 keV—and reproduces across three independent random seeds (per-seed significance $10.9-11.7\sigma$ at 1 keV). Because Al-ending trajectories make up $79\%\text{–}83\%$ of the backscattered population, the inversion also persists in the integrated signal $(P_d/P_m=0.59–0.80)$ despite the oppositely ordered minority O sublattice. The inversion is robust to a $\pm 30\%$ variation of the Hagstrum velocity parameter and survives detector-window selection. Tracking the recorded collision pairs reveals the cause: two Al atoms in the same atomic plane make up $52\%\text{–}72\%$ of the dual events in $\alpha \text{−}{\mathrm{Al}}_2{\mathrm{O}}_3$ (the fraction rising toward low energy; $\langle \left|\mathrm{\Delta }z\right|\rangle =0.29\AA$, small compared with the interlayer spacing), clustering at three characteristic in-plane separations of $\approx 2.6$, 4.7, and 7.1 Å that correspond to the first, second, and fourth Al-Al neighbor shells of corundum. Such a near-grazing intralayer trajectory remains within the high-density surface region considerably longer than a steep multicollision excursion, which enhances neutralization at the second encounter. These results indicate that quantitative regime-resolved charge-fraction analysis in ${\mathrm{He}}^{+}$ LEIS, while suggested by recent measurements on ${\mathrm{CaSiO}}_3$, must in general account for lattice topology and sublattice composition rather than collision count alone.

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• Atom or molecule scattering from surfaces
• Charge-transfer collisions
• Interatomic & molecular potentials
• Ion scattering from surfaces
• Monte Carlo methods