Fig. 2. Nanoparticle shape and surface strain for different gas conditions.

(A) Top and side views of the reconstructed nanoparticle and (B) strain field ϵ_zz at the nanoparticle surface for gas conditions (I to IV). The position of the surface is defined as a cut at 55% of the reconstructed crystalline electron density from its maximum value. (C) Inlet gas composition and mass spectrometer signal during the experiment: CO (blue), O₂ (black), and CO₂ (red).