Global Analytic Potential Energy Surface of <scp>PH₂</scp>⁺ (<scp>1³A</scp>″) and Dynamics Studies of the P⁺(<scp>³P</scp>) + <scp>D₂</scp> Reaction

ABSTRACT The global potential energy surface (PES) of PH 2 + (1 3 A″) was constructed using permutation invariant polynomial neural network method based on 18 566 ab initio energy points. In ab initio calculation, aug‐cc‐pVQZ and aug‐cc‐pwCVQZ basis sets were used for H and P + , respectively. The topographic features of the PES were discussed in detail and compared with available theoretical and experimental values. The results indicate that the PES is well fitted by using neural network method. In addition, quasi‐classical trajectory (QCT) calculations were carried out for the P + ( 3 P) + D 2 reaction in the collision energy range from 1.2 to 8.0 eV. The integral cross sections were reported and compared with experimental data. The differential cross sections were also calculated, and it reflects that the “complex‐forming” mechanism dominates the reaction in the low collision energy range, and direct abstraction mechanism plays a dominant role in the high collision energy range.