Preparation and properties of vanadyl(IV) hypophosphite, VO(PO2H2)2·H2O

Three different phosphate structures, α-K2Mo2P2O11, β-K2Mo2P2O11 and CdMoPO6, in which molybdenum(V) octahedra are assembled in different ways, have been studied by vibrational spectroscopy techniques. A correlation is given between crystal structure and infrared and Raman band behaviour which allows identification of vibrational modes sensitive to a particular configuration of molybdenum species. This represents a powerful tool for structure characterisation when amorphous or single layer supported phases are under study.

Vibrational spectra study of Mo(V) phosphates as examples of different geometries of dimolybdenyl species

A new dichromium(III) cobalt(II) diphosphate(V) of the formula CoCr2(P2O7)2 was detected in the Co3Cr4(PO4)6–Cr(PO3)3 system. The new compound was obtained as a result of high-temperature solid-state reactions between CoCO3, Cr2O3 and (NH4)2HPO4 as well as between Cr(PO3)3 and Co3Cr4(PO4)6. CoCr2(P2O7)2 was characterized using XRD, DTA and IR methods. Results demonstrated that CoCr2(P2O7)2 crystallizes in the triclinic system and its unit cell parameters were calculated. Its infrared spectrum was presented. CoCr2(P2O7)2 melts incongruently at 1270±10 °C with a formation of solid α-CrPO4. The compound Co3Cr4(PO4)6, component of the system under study, was obtained for the first time as a pure phase. Its thermal stability was also investigated. Co3Cr4(PO4)6 is stable in air up to 1410 ± 20 °C.

/pdf/high-temperature-reactions-in-the-co-3-cr-4-po-4-6-cr-po-3-3-1ktnxsyqdy.pdf

High-temperature reactions in the Co 3 Cr 4 (PO 4 ) 6 –Cr(PO 3 ) 3 system

Etude vibrationnelle des monophosphates SrM2(PO4)2 avec M=Co, Ni

Diphosphate as a bidentate ligand. spectroscopic study of the bis(ethylenediamine)diphosphatocobaltate(iii) anion

Das Festkorper-IR-Spektrum von Ba[Co(en)2P2O7]2 · 4 H2O und das Absorptionsspektrum im sichtbaren Spektralbereich einer wasrigen Losung des Komplexes wurden aufgenommen. Die Schwingungs-, Bindungs- und Koordinationseigenschaften der zweizahnigen P2O74− Gruppierung werden kurz besprochen.

A. S. B. Etcheverry

Papers

Diphosphat als zweizähniger Ligand Spektroskopische Untersuchung des Bis(ethylendia min)‐diphosphatocobaltat(III)‐Anions