(a) Averaged O K and Co L_2,3 spectra from the bright stripe (red) and dark stripe (blue), scaled for presentation purposes. (b) Superstructure at higher magnification. Inset: area used for spectrum imaging along with the O K image (false color) generated by integrating PCA-treated spectra over a 30-eV window, after background subtraction. The acquisition time is 1.5 s per pixel. (c) Simulated O K edges for the O3 (red) and O1 (blue) atoms for the La_0.5Sr_0.5CoO_2.25 compound (top) along with the Co 3d PDOS for Co1 (blue) and Co2 (red) (bottom). Reproduced from Ref. [48].