Enrichment of Network Diagrams for Potential Surfaces

Traditional network diagrams connect nodes with simple lines. When one uses them to help interpret complex potential surfaces, that information, the links between minima, is not sufficient to give insights into the dynamics that can occur on those surfaces. Here, we introduce a simple means to introduce more information into the network diagram. Specifically, since each node represents a local potential minimum, the line that links two nodes can be considered a representation of the minimum-energy path between those minima. Then one can add a point along the link, for example, the midpoint, so the link then consists of two segments, one from each minimum to the saddle point of the lowest-energy path connecting them. That makes it possible to represent the energy, at least in terms of energy bands, by coloring each segment from minimum to saddle. We here show examples of such color-coded network diagrams for two illustrative atomic clusters.