Syntheses and Crystal Structures of Three Organically Templated Gallium Phosphates

Abstract

Three open‐framework gallium phosphates [C6H16N2][Ga(HPO4)(PO4)] (1), {H[C6H16N2]2[Ga7(OH)2(PO4)8]} (2), and {H[C4H12N2]2[Ga7(OH)2(PO4)8]·2H2O} (3) were solvothermally synthesized in the presence of 2,6‐dimethylpyrazine, N‐ethylpiperazine, and piperazine as templates, respectively. Compound 1 possesses an infinite one‐dimensional chain structure connected by hydrogen‐bond interactions to generate a 3D supramolecular framework. Compounds 2 and 3 show similar inorganic framework structures, which may be viewed as the assembly of a secondary building unit (SBU), Ga6P8 containing two GaO4, two GaO5, two GaO6 as well as eight PO4 groups. The SBUs are linked with each other by vertex‐sharing oxygen atoms to form 2D sheets, which are further connected by GaO4 tetrahedra to result in the final 3D open‐framework with left‐ and right‐handed helical chains. In these materials, the well‐ordered organic species reside in the voids of structures and interact with the framework by way of hydrogen bonds.

Further Example of Diphosphates: Synthesis and Characterization of K2Li2P2O7

“…The fundamental building units of phosphates are the PO 4 tetrahedra, which exhibit various coordination environments by altering the P–O bond lengths. Additionally, the PO 4 units may be further interconnected through common corners to form complex anionic structures such as isolated species, oligomers, infinite chains, layers, and networks . Owing to the structural diversity, phosphates play an irreplaceable role in many fields, for instance, tissue engineering, optical materials, electrode materials, ionic conductors, and catalysts .…”