Orientation and alignment effects for capture in multiply charged-ion–atom collisions

The shape and the dynamics of the electron charge cloud for capture to the 2p states in ${\mathrm{B}}^{3+}$-He collisions have been studied by coupled-channel methods. We predict strong propensity for electron capture into oriented 2p states, characterized by preferred angular momentum perpendicular to the collision plane. This effect, present for velocities above 0.1 a.u. and intermediate impact parameters, is probably a general aspect of capture to multiply charged ions dominated by p-state capture. A new feature of reaction dynamics is a slippage phenomenon, i.e., the major axis of the 2p charge density lags behind the internuclear axis as the projectile traverses the turning point.