URVAvis: A Graphical User Interface for the Visual Mechanistic Analysis of Chemical Reactions Based on the Unified...

The Unified Reaction Valley Approach (URVA) enables the precise mechanistic analysis of chemical reactions through the detailed examination of the reaction path (RP) traced by the reaction complex (RC) on the potential energy surface. In this approach, the curvature of the RP is decomposed into curvature components tied to changes in the RC's internal coordinates during a given reaction (e.g., changes in bond lengths, bond angles, or dihedral angles). The RP curvature decomposition is then analyzed to identify the reaction's key mechanistic events. However, this curvature decomposition analysis involves a fragmented and often time-consuming computational workflow requiring multiple visualization software. To address this analysis limitation, the URVAvis graphical user interface is introduced herein. URVAvis enables the user to visualize the data necessary for the curvature decomposition analysis in a single, integrated platform, thereby streamlining this analysis workflow and enhancing the practical usability of URVA for mechanistic studies. The capabilities of URVAvis are demonstrated for an elementary step of the astrochemically relevant gas-phase reaction between acetonitrile (CH3CN) and the carbon monochloride ion (CCl+). Through the URVAvis-facilitated analysis of the elementary step's RP curvature decomposition, essential mechanistic events of the reaction are elucidated.