At low oxygen ratios, the interaction is mostly formed by surface oxygen atoms on 2-fold, 3-fold or 4-fold coordinated sites. As the oxygen ratio increases, the interaction is increasingly dominated by subsurface oxygen atoms, characterized by square-planar interactions with short bond distances (≤ 2.0 Å), indicating a Pt 3 O 4 stoichiometry. At higher oxygen ratios, a PtO 2 stoichiometry was identified by the formation of PtO 6 octahedrons with two short Pt-O bonds (≈ 2.0 Å) and four longer bonds (≈ 2.05 Å). Locally distinguishing specific phases among the various stoichiometries is challenging and would require detailed analysis using specific descriptors such as the Smooth Overlap of Atomic Positions (SOAP). We attempted to perform classification using such descriptors, but did not reach a valid conclusion, with various configurations showing similarity to multiple phases. This indicates transitional systems with no long-range ordering of the oxide-like phase, and the possibility of multiple phases anchored by dangling oxygen atoms.