A zinc phosphate possessing ladder-like layers made up of three-and four-membered rings and infinite Zn-O-Zn chains

Abstract

A new open-framework zinc phosphate, [NH₃(CH₂)₂NH(CH₂)₂NH₃]²⁺2[Zn₂PO₄(HPO₄)]^-, possessing a layered architecture and consisting of alternating inorganic and organic layers, stabilized by multipoint hydrogen bonding has been synthesized hydrothermally. It has the following crystal data: monoclinic space group C2/c, a = 25.075(5) Å, b = 5.127(1) Å, c = 17.726(4) Å, β = 125.4(1)°, V = 1857.6(6) ų, Z = 8, M = 748.3(1), D_calc = 2.06 g cm^-3, MoKα, and R_F = 0.04. The structure is made up of ZnO₄ and PO₄ tetrahedra linked though vertexes. The connectivity between the two units creates a layered structure with steps, the layers consisting of three- and four-membered rings only. This is the first instance of such a network in open-framework zinc phosphates. The exclusive presence of three-membered ring chains creates steps in the layers as well as an infinite number of Zn-O-Zn one-dimensional chains. Hydrogen bond interactions between the inorganic layers give rise to pseudo 10-membered ring channels, in which the diprotonated diethyelenetriamine molecules reside. The unusual T atom (T being Zn or P) connectivity in this material suggests the possibility of synthesizing many such materials with novel connectivities and networks.