In Figure we show the Ih 309 NP in its ideal configuration (at 0 K: after minimization) and at various temperatures (top-tobottom: 300 K, 400 K, 500 K). In particular, the Ih 309 snapshots at 300 K, 400 K, 500 K correspond to the same MD frames of Figure , and Figure and, but in Figure the atoms are colored based on the similarity of their atomic environments and those contained in the SOAP dictionary of Figure (top-down analysis). This analysis allows us to track in detail which ones of the AEs populating the Ih 309 NP at the various temperature belong to the family of the native ones, typical of icosahedral NPs, and which ones are non-native -namely, closer to those natives of different shape NPs, such as e.g., decahedra or truncated octahedra. For each NP snapshot, a pie chart (bottom-right) shows the percentage of surface atoms belonging to native (in gray) and non-native AEs (in pink) in the Ih 309 . The analysis shows how the percentage of emerging non-native environments increases with increasing temperature, essentially due to increased thermal fluctuations and surface reconstructions.