Fig. 4: XANES Simulation for geometric structure analysis.

a Cu K-edge XANES experimental spectra of the sample under ex situ condition and −0.6 V and the calculated spectra for Cu atoms at the corner, edge, (100) plane, and (111) plane and corresponding configurations. b Schematic for the coordination number of Cu atoms at different sites and the surface migration of single Cu atoms under working conditions⁵⁰ (a, b reproduced with permission from ref. ⁵⁰. Copyright 2020, American Chemical Society). c Set of possible deformations applied to the structure models used for the construction of the SML training data set and XANES fitting. d Representative calculated XANES spectra for models 1–3⁵¹ (c, d reproduced with permission from ref. ⁵¹. Copyright 2023, American Chemical Society).