A new global potential energy surface of the ground state of SiH₂⁺ (X²A₁) system and dynamics calculations of the Si⁺ + H₂ (v₀ = 2, j₀ = 0) → SiH⁺ + H reaction

A global potential energy surface (PES) of the ground state of SiH_2^+ system is built by using neural network method based on 18223 ab initio points. The topographic properties of PES are presented and compared with previous theoretical and experimental studies. The results indicate that the spectroscopic parameters obtained from the new PES are in good agreement with the experimental data. In order to further verify the validity of the new PES, a test dynamics calculation of the Si^+ + H_2 (v_0 = 2, j_0 = 0) \to H + SiH^+ reaction has been carried out by using the time-dependent wave packet method. The integral cross sections and rate constants are computed for the title reaction. The reasonable dynamical behavior indicates that the newly constructed PES is suitable for relevant dynamics investigations.