Fig. 2: The transition from full to sparse representation for an example MoS2 supercell.
From: Sparse representation for machine learning the properties of defects in 2D materials
a A full MoS2 structure with one Mo → W, two S → Se substitutions, and two S vacancies; b sparse representation, containing only defects types and coodrinates; c intermediate point of the graph construction: cutoff radius centered on the metal substitution defect; d the final graph with sparse representation. A dashed green line indicates a virtual graph edge that effectively connects one node with another via a periodic boundary condition.
