PES-trotter: A Cross-Platform Open-Source Application for the Analysis of Molecular Processes on 3D Potential-Energy...

We present PES-trotter, a cross-platform application for the exploration and analysis of 3D potential-energy landscapes generated from multi-dimensional potential-energy surfaces (PESs) of molecular systems. Inspired by the main ideas behind the previously released software AVATAR (Martino et al., Journal of Computational Chemistry 41 (2020): 1310-1323) relying on virtual-reality technology and third-party commercial software, PES-trotter is based on the open-source game engine Godot and related open-source assets, and introduces radically new important features for the navigation and topological analysis of the PES, among which the possibility of (1) navigating in walk, fly or free-mouse mode, (2) plotting energy profiles from custom curvilinear paths, (3) computing critical points and minimum-energy paths, and (4) playing back dynamical trajectories in first-person ride or spectator mode. Designed to match high portability and adaptability, PES-trotter can be run either as a stand-alone application on Windows, Linux, Android and macOS operating systems or in the window of a simple web browser on devices as widespread as mobile phones. In the article, the main features of PES-trotter are thoroughly described through two illustrative applications (the conformational analysis of a functionalized glycine and the analysis of classical trajectories for the H + LiH⁺ $\to$ H₂ + Li⁺ reactive process) highlighting the versatilty of PES-trotter as an innovative and accessible tool supporting chemical research and education.