Local structural features around Mn and Fe in Mn-bearing andalusite from Västanåberget, Sweden were investigated by anomalous X-ray scattering (AXS) and X-ray absorption fine structure (XAFS). The X-ray absorption near edge structure (XANES) spectra indicate that all of the Mn and Fe atoms are in +3 oxidation state. Both the electron density map of Mn obtained by AXS and simulated multiple-scattering extended X-ray absorption fine structure (EXAFS) spectra indicate that the Mn atoms exclusively

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... occupy Al1 sites. Further, the EXAFS analysis indicates that the first neighbor coordinated to Mn at the Al1 site shows a complete structural relaxation and Jahn-Teller distortion owing to Mn 3+ . In addition, the EXAFS analyses reveal that Fe occupies both Al1 and Al2 sites. The Fe site occupancy ratio (Fe at Al2 to total Fe) in the Mn-bearing andalusite sample is 40-50%. Employing the local structural information around Mn and Fe, a conventional single-crystal structural refinement converged at R = 2.34% with a structural formula of (Al 0.82 Mn 0.16 Fe 0.02 ) [6] (Al 0.99 Fe 0.01 ) [5] SiO 5 (space group Pnnm with a = 7.8538(9), b = 7.9463(9), c = 5.5867(6) Å).