Credit: Heather Kulik et al, MIT
Multi-reference character of 3,165 structures as evaluated by two of the 15 diagnostics used by experts in the field, nHOMO[MP2] (top left) and C02 (top right). Bottom panels show all 15 diagnostics displayed using the uniform manifold approximation and projection (UMAP), with the bottom/top 10 percent for the two metrics shown as solid blue/red circles. This machine learning approach makes it possible to predict multi-reference character and determine whether computationally inexpensive techniques such as density functional theory (DFT) are sufficient.