Synthesis, Structural Study of Non-centrosymmetric NaH2(PO4)0.48(AsO4)0.52·H2O crystal

摘要

The salt NaH₂(PO₄)_0.48(AsO₄)_0.52·H₂O (abbreviated as NDAP) derives from the NaH₂PO₄·H₂O-NaH₂AsO₄·H₂O system. The structural characteristics of the crystals were analyzed by means of X-ray diffraction, and solved from 3737 independent reflections with R₁ = 0.019 and Rw₂ = 0.045, then refined with 84 parameters. The following results have been obtained: space group P2₁2₁2₁, a = 5.1383(5)Å, b = 8.3301(8)Å, c = 10.2492(10)Å and Z = 4. The crystal structure of NDAP is built up from a discrete tetrahedral P(As)O₄3- connected with O-H…O hydrogen bonds and through the electrostatic actions of Na+ cations.