Mapping inorganic crystal chemical space

The combination of elements from the Periodic Table defines a vast chemical space. Only a small fraction of these combinations yield materials that occur naturally or are accessible synthetically. Here, we enumerate binary, ternary, and quaternary element combinations to produce an extensive library of over 10^10 stoichiometric inorganic compositions. The unique combinations are vectorised using compositional embeddings drawn from a variety of published machine-learning models. Dimensionality reduction techniques are employed to present a two-dimensional representation of inorganic crystal-chemical space, which is labelled according to whether they pass standard chemical filters and if they appear in known materials databases.