CRYSTAL-STRUCTURE DETERMINATION OF ALVMOO7 FROM X-RAY-POWDER DIFFRACTION DATA

The structure of AlVMoO7 was solved by direct methods from high resolu tion X-ray powder diffraction data and refined by the Rietveld method. The lattice constants are a=5.3763(3)Angstrom, b=8.1644(3)Angstrom an d c=12.7312 Angstrom. Space group Pmcn followed from the systematic ex tinctions and was confirmed by the successful structure solution. Alum inum is octahedrally coordinated by oxygen, whereas vanadium possesses a distorted pyramidal coordination and molybdenum is tetrahedrally co ordinated by oxygen atoms. A three dimensional framework structure res ults from corner and edge connection of the coordination polyhedra. VO 5 pyramids are edge linked to infinite (VO2+)(infinity) chains. Theref ore, AlVMoO7 can be classified as a polyvanadate.