Iridium L₃-edge XAS dataset of natural Ir-O phase, comprising IrO₂

This dataset contains Ir L₃-edge X-ray Absorption Spectroscopy (XAS) data supporting Figures 5–7 of the associated manuscript. It includes normalized XANES spectra (Figure 5), linear combination fitting (LCF) results (Figure 6), and background-subtracted k²-weighted EXAFS spectra with Fourier transforms and Artemis fit outputs (Figure 7) for Ir-bearing samples POI-I through POI-IV. Reference spectra (e.g., Ir@Ir, Ir@Pt, Ir@IrO₂) used in FDMNES simulations are also included. The dataset was collected at the BM23 beamline at ESRF and processed using Athena and Artemis software.