| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1506302 | Solid State Sciences | 2008 | 7 Pages |
Synthesis, structure refinement and thermal behaviour are reported for a new diphosphate HHoP2O7·3H2O. This salt crystallizes in the triclinic system with space group P1¯and with lattice parameters: a = 6.425(5), b = 6.912(5), c = 9.809(5) Å; α = 81.554(5)°, β = 80.329(5)°, γ = 88.485(5)° and Z = 2. The crystal structure is refined to R = 0.0443 using 859 reflections. The corresponding atomic arrangement is built up by thick layers of HP2O73− anions and HoO8 polyhedra parallel to the (ab) plane.IR and Raman spectra of the HHoP2O7·3H2O are interpreted on the basis of characteristic vibrations of O–H and P2O7 groups. No coincidence of most of Raman and IR band positions confirm the centrosymmetric structure for this salt. TG and DTA investigations show that the elimination of the crystallization water takes place in two stages between 30 and 340 °C. The stability of the anhydrous salt is very limited. It decomposes between 340 and 900 °C to give Ho2P4O13.The holmium orthophosphate HoPO4 (Xenotime) is obtained when heating HHoP2O7·3H2O in a static air furnace at 1200 °C.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide
