OH-Formation Following Vibrationally Induced Reaction Dynamics of H$_2$COO

• DOI: 10.48550/arxiv.2402.10047
• Publication Date: 2024-02-15
• Authors: K. Song; Meenu Upadhyay; Markus Meuwly
• Keywords: Dynamics; Reaction dynamics

The reaction dynamics of H$_2$COO to form linear HCOOH and dioxirane as first steps for OH-elimination is quantitatively investigated. Using a machine learned potential energy surface at the CASPT2/aug-cc-pVTZ level theory vibrational excitation along CH-normal mode $\nu_{\rm CH}$ with energies up 40.0 kcal/mol ($\sim 5 \nu_{\rm CH}$) leads almost exclusively which further decomposes into OH+HCO. Although barrier only 21.4 probability two orders magnitude lower if CH-stretch excited. Following dioxirane-formation pathway facile, however, in addition COO-bend vibration excited equivalent $\sim (2 CH} + 4 COO})$ or (3 COO})$. For OH-formation atmosphere through probably most relevant because alternative pathways (through formic acid) involve several intermediates that can de-excite collisions, relax {\it via} Intramolecular redistribution (IVR), pass very loose vulnerable transition states (formic acid). This work demonstrates how, by selectively exciting particular modes, it possible dial desired channels high degree specificity process atmospheric chemistry.