Testing standard basis sets for direct ionizations: H+ + H at ELab =0.1–100keV

• Published in: Journal of computational chemistry Vol. 45; no. 10; pp. 671 - 682
• Main Authors: Kim, Hyunsik, Morales, Jorge A
• Format: Journal Article
• Language: English
• Published: New York Wiley Subscription Services, Inc 01.04.2024
• Subjects: Charge transfer; Electrons; Simulation
• ISSN: 0192-8651; 1096-987X
• DOI: 10.1002/jcc.27272

With the simplest‐level electron nuclear dynamics (SLEND) method, we test standard Slater‐type‐orbital/contracted‐Gaussian‐functions (STO/CGFs) basis sets for the simulation of direct ionizations (DIs), charge transfers (CTs), and target excitations (TEs) in H+ + H at ELab = 0.1–100 keV. SLEND is a time‐dependent, variational, on‐the‐fly, and nonadiabatic method that treats nuclei and electrons with classical dynamics and a Thouless single‐determinantal state, respectively. While previous tests for CTs and TEs exist, this is the first SLEND/STO/CGFs test for challenging DIs. Spin‐orbitals with negative/positive energies are treated as bound/unbound states for bound‐to‐bound (CT and TE) and bound‐to‐unbound (DI) transitions. SLEND/STO/CGFs simulations correctly reproduce all the features of DIs, CTs and TEs over all the considered impact parameters and energies. SLEND/STO/CGFs simulations correctly predict CT integrals cross‐sections (ICSs) over all the considered energies and predict satisfactory DI and TE ICSs within some energy ranges. Strategies to improve SLEND/STO/CGFs for DI predictions are discussed.