Aluminium dihydrogenphosphate explained

Aluminium dihydrogenphosphate describes inorganic compounds with the formula Al(H2PO4)3.xH2O where x = 0 or 3. They are white solids. Upon heating these materials convert sequentially to a family of related polyphosphate salts including aluminium triphosphate (AlH2P3O10.2H2O), aluminium hexametaphosphate (Al2P6O18), and aluminium tetrametaphosphate (Al4(P4O12)3). Some of these materials are used for fireproofing and as ingredients in specialized glasses.[1]

According to analysis by X-ray crystallography, the structure consists of a coordination polymer featuring octahedral Al3+ centers bridged by tetrahedral dihydrogen phosphate ligands. The dihydrogen phosphate ligands are bound to Al3+ as monodentate ligands.[2]

References

  1. Encyclopedia: Klaus Schrödter . Gerhard Bettermann . Thomas Staffel . Friedrich Wahl . Thomas Klein . Thomas Hofmann. Phosphoric Acid and Phosphates. Ullmann's Encyclopedia of Industrial Chemistry. 2008. Wiley-VCH. Weinheim. 10.1002/14356007.a19_465.pub3. 978-3527306732 . 94458523 .
  2. Eine neue Form von Al(H2PO4)3 mit dreidimensionaler Al-O-P Vernetzung. A new form of Al(H2PO4)3 with three-dimensional Al-O-P crosslinking. Brodalla, D. . Kniep, R. . Mootz, D.. Zeitschrift für Naturforschung B . 36. 1981. 907–909. 10.1515/znb-1981-0803. free.