Synthesis and structure of a zinc oxalate with honeycomb layers and zinc phosphates with one-and three-dimensional structures

Three new compounds, a zinc oxalate I, [(CH3)2NH(CH2)3NH3] [Zn2(C2O4)3].2H2O, and two zinc phosphates II, [(CH3)2NH(CH2)3NH3] [Zn(HPO4)2]·H2O, and III, [(CH3)2NH(CH2)3NH3] [(ZnPO4)2]·2H2O, have been synthesized by solvothermal reactions in the presence of N,N-dimethyl-1,3-diaminopropane. While I has a honeycomb zinc oxalate layers with 12-membered apertures (6 Zn and 6 oxalates), II has a one-dimensional corner-shared 4-membered ring (Zn2P2O4) zinc phosphate chains, and III has a three-dimensional zinc phosphate structure. The structure of III resembles the aluminosilicate zeolite, thomsonite. The formation of these open-framework solids appears to depend on the relative concentrations of the amine and phosphoric acid in the synthesis mixture