Assembly of one-dimensional AlP2O83– chains into three-dimensional MAlP2O8·C2N2H9 frameworks through transition metal cations (M = Ni2+, Co2+ and Fe2+)

Three-dimensional (3D) MAlP2O8·C2N2H9 open-frameworks have been successfully generated from 1D AlP2O83– chains using transition metal cations M2+(M = Ni, Co and Fe). The 1D AlP2O83– chain compound whose chain structure is made up of corner-sharing Al2P2 four-membered rings is prepared solvothermally using ethylenediamine as a template; to the reactant mixture in which the one-dimensional AlP2O83– chain compound has already crystallized, transition metal cations are added. Structural analysis indicates that the terminal oxygen atoms attached to the one-dimensional AlP2O83– chains are exclusively coordinated to M2+ forming O–M–O bonds. XRD, DRS, ICP, CHN and M?ssbauer techniques have been used to characterise the products. This work provides a new approach to the synthesis of 3D open-frameworks through the assembly of low-dimensional structures via transition metal cations.