Rietveld refinement of a natural cobaltian mansfieldite from synchrotron data

• Main Authors: Giovanni Pratesi, Matteo Zoppi
• Format: Article
• Language: English
• Published: International Union of Crystallography 2009-02-01
• Series: Acta Crystallographica Section E
• Online Access: http://scripts.iucr.org/cgi-bin/paper?S1600536808044127

A structural refinement of a natural sample of a Co-bearing mansfieldite, AlAsO4·2H2O [aluminium orthoarsenate(V) dihydrate], has been performed based on synchrotron powder diffraction data, with 5% of the octahedral Al sites replaced by Co. Mansfieldite is the aluminium analogue and an isotype of the mineral scorodite (FeAsO4·2H2O), with which it forms a solid solution. The framework structure is based on AsO4 tetrahedra sharing their vertices with AlO4(H2O)2 octahedra. Three of the four H atoms belonging to the two water molecules in cis positions take part in O—H...O hydrogen bonding.