A Quantum Time‐Dependent Wave Packet Study on Be ⁺ ( ² S ) + 

ABSTRACT

The interactions of the Be ⁺ ion with the H ₂ molecule and its isotopic variants are important for quantum information and ultracold chemistry. We performed quantum dynamics calculations for the Be ⁺ ( ² S) + HD → BeH ⁺ /BeD ⁺  + D/H reaction using the time‐dependent wave packet method, based on the newly constructed ground‐state BeH ₂ ⁺ potential energy surface (Molecules, 2024, 29, 3436). Strong intramolecular isotope effects and different dynamic mechanisms are seen on the two reaction channels. Reaction probabilities and branching ratios show that the formation of BeD ⁺ is strongly preferred throughout the entire investigated energy range. At relatively high collision energies, the differential cross sections show nearly forward‐backward symmetric scattering for the BeD ⁺  + H channel, while the BeH ⁺  + D channel exhibits forward scattering. Rovibrationally resolved integral cross sections show that the BeD ⁺ product mainly populates low‐vibrational, high‐rotational states, while the BeH ⁺ product exhibits a vibrationally hot and rotationally cold distribution. The quantum dynamics results show that the BeD ⁺  + H channel follows a complex‐forming mechanism, while the BeH ⁺ product is mainly generated through a direct abstraction mechanism. The dynamics data presented here could serve as a reference for finer experimental studies of the Be ⁺ ( ² S) + HD reaction.