Crystallization of ultraphosphates via the gas phase. The crystal structures of FeP4O11, ZnP4O11 and CdP4O11
摘要:
The new ultraphosphates FeP4O11, ZnP4O11 and CdP4O11 of the CuP4O11 structure type were synthesized from the corresponding meta- or polyphosphates and P4O10. Crystallization via the gas phase has been achieved at elevated temperatures using a mixture of P (3 mg) and I-2 (50 mg) as mineralizer. The crystal structure consists of a two-dimensional phosphate network, built from four crystallographically independent 10-membered polyphosphate rings. Each ring contains four secondary and six tertiary PO4-groups. Two crystallographically independent metal sites showing sixfold coordination by terminal oxygen atoms are located inbetween the phosphate layers. FeO6-octahedra (2.028(3) Angstrom < (d) over bar FeO6 < 2.268(3) Angstrom) and ZnO6 octahedra (2.002(2) Angstrom < (d) over bar ZnO6 < 2.256(2) Angstrom) exhibit slightly larger radial distortion than the CdO6-octahedra (2.215(7) Angstrom < (d) over bar CdO6 < 2.383(3) Angstrom).