ElementKG 2.0

ElementKG 2.0 is a chemistry knowledge graph that spans the entire chain from “elements–functional groups–molecules–reactions–experiments,” aiming to model the full lifecycle of chemical reactions. Its node types include atoms, functional groups, molecular categories, specific compounds, reaction types, experimental steps, reagents, and instruments. It supports tasks such as molecular classification (e.g., by functional groups), tautomerism, reaction condition inference, and experiment-procedure reasoning. The graph currently integrates more than 10 million molecular entities and incorporates structural, property, and reaction data from sources such as PubChem and the Open Reaction Database. It can be used to train knowledge-enhanced chemical large models or agents, improving interpretability and reliability in tasks including reaction prediction, retrosynthesis planning, and experimental protocol generation.