摘要:
This paper describes the syntheses of three transition metal diphosphonate compounds: Na4Zn{NH3CH(PO3)(2)}(2) center dot 4H(2)O (1), Ni{NH3CH(PO3H)(2)}(2)center dot xH(2)O (2) and NaNi2{NH3CH(PO3)(PO3H0 (5))}(2)(H2O)(2)center dot 2H(2)O (3). Compound 1 contains chains of [Zn(NH3CH(PO3)(2)}(2)](n)(4n-) made up of corner-sharing ZnO6 octahedra and CPO3 tetrahedra, which are further connected by tetramers of edge-sharing NaO6 octahedra, forming a three-dimensional open-framework structure. Compound 2 shows a square-grid layer structure where the NiO6 octahedra are corner shared with CPO3 tetrahedra. The adjacent layers are linked by strong interlayer hydrogen bonds, resulting in a three-dimensional open-network structure with channels where the lattice water molecules reside. The structure of compound 3 is analogous to that of NaCo2{NH3CH(PO3)(PO3H0.5)}(2)(H2O)(2)center dot xH(2)O in which layers of Ni-2{NH3CH(PO3)(PO3H0.5)}(2)(H2O)(2) are connected by NaO6 linkages into an open-framework structure. The magnetic studies show that weak antiferromagnetic interactions are mediated between the nickel ions in compounds 2 and 3. Crystal data for 1: triclinic, space group P-1, a = 5.551(2) angstrom, b = 6.166(2) angstrom, c = 12.424(4) angstrom, alpha = 92.422(6)degrees, beta = 92.687(7)degrees, gamma = 93.926(6)degrees, V = 423.3(2) angstrom(3), Z = 2. For 2: triclinic, space group P-1, a = 9.043(1) angstrom, b = 9.180(1) angstrom, c = 9.271(1) angstrom, alpha = 89.693(3)degrees, beta = 70.202(3)degrees, gamma = 89.530(3)degrees, V = 724.1(2) angstrom(3), Z = 2. (C) 2005 Elsevier Inc. All rights reserved.