The crystal structure of metarossite, ideally CaV2O6·2H2O [chemical name: calcium divanadium(V) hexaoxide dihydrate], was first determined using precession photographs, with fixed isotropic displacement parameters and without locating the positions of the H atoms, leading to a reliability factor R = 0.11 [Kelsey & Barnes (1960). Can. Mineral. 6, 448-466]. This communication reports a structure redetermination of this mineral on the basis of single-crystal X-ray diffraction data of a natural sample from the Blue Cap mine, San Juan County, Utah, USA (R1 = 0.036). Our study not only confirms the structural topology reported in the previous study, but also makes possible the refinement of all non-H atoms with anisotropic displacement parameters and all H atoms located. The metarossite structure is characterized by chains of edge-sharing [CaO8] polyhedra parallel to  that are themselves connected by chains of alternating [VO5] trigonal bipyramids parallel to . The two H2O molecules are bonded to Ca. Analysis of the displacement parameters show that the [VO5] chains librate around . In addition, we measured the Raman spectrum of metarossite and compared it with IR and Raman data previously reported. Moreover, heating of metarossite led to a loss of water, which results in a transformation to the brannerite-type structure, CaV2O6, implying a possible dehydration pathway for the compounds M 2+V2O6·xH2O, with M = Cu, Cd, Mg or Mn, and x = 2 or 4.
|Original language||English (US)|
|Number of pages||5|
|Journal||Acta Crystallographica Section E: Crystallographic Communications|
|State||Published - 2016|
- crystal structure
- hydrogen bonds
- phase transformation
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
FingerprintDive into the research topics of 'Redetermination of metarossite, CaV5+ 2O6·2H2O'. Together they form a unique fingerprint.
CCDC 1497229: Experimental Crystal Structure Determination
Kobsch, A. (Creator), Downs, R. T. (Creator) & Domanik, K. J. (Creator), Cambridge Crystallographic Data Centre, 2016
DOI: 10.5517/ccdc.csd.cc1m7zqk, http://www.ccdc.cam.ac.uk/services/structure_request?id=doi:10.5517/ccdc.csd.cc1m7zqk&sid=DataCite