Crystal Structure of the Yttrium‐Ammonium Polyphosphate YNH₄(PO₃)₄

Abstract

Abstract Crystal chemistry and structural analysis are described for the yttrium‐ammonium polyphosphate: YNH 4 (PO 3 ) 4 . The orthorhombic unit cell has the dimensions: a = 11.927(9), b = 10.357(8), c = 17.309(15) Å. Space group is C222 1 with Z = 8. Crystal structure has been solved by using 1815 independent reflections with a final R value of 0.037. The unit cell contains two (PO 3 ) ∞ chains related by a 2 1 axis parallel to c. The outstanding features of each chain are the existence of two perpendicular twofold axes and a period of 16 PO 4 tetrahedra. YNH 4 (PO 3 ) 4 provides the first example of a (PO 3 ) ∞ chain with such a large period.