Transformations of a layer and a chain aluminophosphates to the zeotype ∣Al–P–M–O∣– GIS (M = Co 2+, Mn 2+, Mg 2+)

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A two-dimensional (2-D) layer aluminophosphate ∣(C 2H 8N) 2∣[Al 2(HPO 4)(PO 4) 2] ( 1) and a 1-D chain aluminophosphate ∣NH 3CH 2CH 2NH 3∣[AlP 2O 8H] ( 2) have been prepared in the solvothermal system. In the presence of metal M 2+ cations (M = Co 2+, Mn 2+, Mg 2+), compounds 1 and 2 transform to the 3-D open frameworks of ∣Al–P–M–O∣– GIS. Single-crystal X-ray diffraction, XRD, TG and compositional analyses show that the structures of ∣Al–P–M–O∣– GIS (M = Co 2+, Mn 2+, Mg 2+) are analogous to zeolite gismondine (zeotype GIS) in which 50% metal sites in the framework are occupied by Co 2+, Mn 2+ or Mg 2+ cations, and protonated dimethylamine cations reside in the 8-ring channels. Interestingly, the edge-sharing 4-ring chain (denoted as AlPO-ESC) featured in compounds 1 and 2 remains in the structures of ∣Al–P–M–O∣– GIS. This study not only provides a potential approach to synthesize complex open frameworks through the reaction of low-dimensional precursors with metal cations, but also further suggests that the AlPO-ESC chain might be a basic building unit for the formation of diverse 3-D open-framework structures.