Dingguo Xu

Amine-Ligated Approach for the Synthesis of Extra-Large-Pore Zinc Phosphites with qtz-h and bnn Topologies

Presented here are two open-framework zinc phosphites, namely, Zn(dabco)0.5(HPO3) (SCU-18) and Zn4(Hdabco)2(CH3COO)2(HPO3)4 (SCU-20), where dabco = 1,4-diazabicyclo[2.2.2]octane. SCU-18 features a rare 3-connected inorganic skeleton with a chiral qtz-h topology. It contains 18-membered-ring (18 MR) channels displaying porosity and second-harmonic-generation response. SCU-20 has a bnn topology containing large 20 MR channels that shows a strong blue emission as a result of excitation at 375 nm.

Open-framework beryllium phosphates with a zeolitic CrB4 topology and their structural analogues containing 12-ring channels

Two new open-framework beryllium phosphates, formulated as MV·Be2(HPO4)2(H2PO4)2 (1) and EV·Be2(HPO4)2(H2PO4)2 (2), have been synthesized under solvothermal conditions, where MV = methylviologen and EV = ethylviologen. The two compounds have large 16-membered ring (16 MR) channels with a zeolitic CrB4 topology. They contain in situ generated viologen dications from the alkylation of 4,4′-bipyridine (4,4′-bpy) molecules as the structure-directing agents (SDAs). In comparison, the use of 4,4′-bpy and 2,2′-bpy as the SDAs results in the formation of two different open-framework compounds, (4,4′-H2bpy)2·Be5(HPO4)7 (3) and (2,2′-H2bpy)0.5·Be3(OH)(HPO4)3 (4). Compounds 3 and 4 have different framework structures with 12 MR channels. The presence of large 41084124 cages in the structure of 3 is worth noting.