RESEARCH / A0299
Secondary Mobility of Arsenic Due to In Situ-Generated Iron–Arsenic Colloids upon Iron Oxide Amendments
Read the original paper · 10.1021/acs.est.5c06458 ↗
Source figures may contain other techniques and soft X-ray spectra. C, N and O measurements are outside our current hard-XAFS testing range.
Figure 3. Fe K-edge (a) XANES, (b) EXAFS, and (c) phase-corrected Fourier-transform EXAFS spectra of Fe−As colloids formed under various conditions. For reference, the patterns of ferrihydrite and lepidocrocite are included in the (a) XANES and (b) EXAFS plots according to the XRD and Cs-STEM results. The results of shell-by-shell fittings are provided in Table S5. (d) Optimized geometries of Fe−As colloids, obtained via density functional theory (DFT) calculations. The Fe−As bond lengths are given in angstroms, and other possible Fe−As colloid structures are shown in Figure S24.