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Two isostructural heterometallic ZrMOFs (denoted as ZrMOF-Co/Ni) were obtained by stepwise sysnthesis approach. Single-crystal X-ray structural analyses indicate that two ZrMOFs are both built from trinuclear zirconocene-based metallo-pyridine buliding blocks, featuring 2D infinite chain structure. Furthermore, the magnetic studies reveal that ZrMOF-Co shows antiferromagnetic performance, while ZrMOF-Ni feature ferromagnetic behavior.

Systematic design and self-assembly of metal-organic polyhedra with predictable configuration has been a long-standing challenge in crystal engineering due to the difficulty of finding suitable building units. Herein, we are focused on a concave polyoxovanadate cluster [V6O6(OCH3)9(SO4)4]5- that can be generated in situ under the exact reaction conditions. Based on this cluster, a potential trivalent molecular building block [V6O6(OCH3)9(SO4)(CO2)3]2- can be obtained by the bridging-ligand-substitution strategy that possesses appropriate angle information for the design of molecular cubes. Utilizing the face-directed assembly of the trivalent molecular building block and a diverse set of tetratopic carboxylate linkers, a series of metal-organic cubes VMOC-1 to VMOC-5 with the same topology but different functionalities and dimensions are designed and constructed. The inclusion study made with VMOC-3 as an example has shown that they are potential molecular receptors and can selectively capture size-matching polycyclic aromatic hydrocarbon guest molecules.

A rational synthetic strategy to construct two supramolecular isomers based on polyoxovanadate organic polyhedra with tetrahedral symmetries is presented. VMOP-α, a low-temperature product, has an extremely large cell volume (470 842 A3 ), which is one of the top three for well-defined MOPs. The corner-to-corner packing of tetrahedra leads to a quite low density of 0.174 g cm-3 with 1D channels (ca. 5.4 nm). The effective pore volume is up to 93.6 % of cell volume, nearly the largest found in MOPs. For the high-temperature outcome, VMOP-β, the cell volume is only 15 513 A3 . The packing mode of tetrahedra is corner-to-face, giving rise to a high-density architecture (1.324 g cm-3 ; channel 0.8 nm). Supramolecular structural transformation between VMOP-α and VMOP-β can be reversibly achieved by temperature-induced solvent-mediated transformation. These findings give a good opportunity for understanding 3D supramolecular aggregation and crystal growth based on large molecular tectonics.

Nanoscale regular polyhedra with icosahedral symmetry exist naturally as exemplified by virus capsids and fullerenes. Nevertheless, their generation by supramolecular chemistry through the linking of 5-fold symmetry vertices remains unmet because of the absence of 5-fold symmetry building blocks with the requisite geometric features. This situation contrasts with that of tetrahedral and octahedral symmetry metal–organic polyhedra (MOPs), for which appropriate triangular and square molecular building blocks (MBBs) that can serve as vertices or faces are readily available. Herein, we report isolation of a pentagonal [WV5O11(SO4)6]8– cluster and reveal its utility to afford the first four examples of nanoscale Goldberg MOPs, based upon 5-fold MBBs. Two 32-faced Gv(1,1) MOPs and two 42-faced Gv(2,0) MOPs were formed using linear or triangular organic ligands, respectively. The largest Goldberg MOP-4, exhibits a diameter of 4.3 nm, can trap fullerene C60 molecules in its interstitial cavities.

Unprecedented Anderson-like alkoxo-polyoxovanadate [V6O6(OCH3)9(μ6-SO4)(COO)3](2-) polyanions can serve as 3-connected second building units (SBUs) that assemble with dicarboxylate or tricarboxylate ligands to form a new family of metal organic tetrahedrons of V4E6 and V4F4 type (V = vertex, E = edge, and F = face). To our knowledge, this alkoxo-polyoxovanadate-based SBU is the first ever reported.

Seven new coordination polymers, namely, [Zn(L)(bdc)]·2H2O (1), [Zn(L)(2-NH2-bdc)]·2H2O (2), [Zn(L)(bdc)]·1.75DMF·0.5H2O (3), [Zn(L)(oba)]·H2O (4), [Co(L)(oba)]·H2O (5), [Cd2(L)2(bdc)(NO3)2]·2DMF (6) and [Cd(L)(ndc)(H2O)] (7) (L = 4-amino-3,5-bis(4-imidazol-1-ylphenyl)-1,2,4-triazole, H2bdc = 1,4-benzenedicarboxylic acid, 2-NH2-H2bdc = 2-amino-1,4-benzenedicarboxylic acid, H2oba = 4,4′-oxydibenzoic acid and H2ndc = 1,4-naphthalenedicarboxylic acid), have been synthesized. The structures were determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR, and thermogravimetric (TG) analysis. 1 and 2 feature a similar three-fold interpenetrating network combined with interdigitation which extends the structure into a three-dimensional framework. 3 is a two-fold interpenetrating framework showing intralayer porosity and interdigitation. Compounds 1 and 3 represent a pair of supramolecular isomers where structural motifs and different interpenetration modes exist; compounds 4 and 5 are isostructural and display the same three-fold interpenetrating framework where two types of interlaced triple-stranded helices A and B can be found. The triple-stranded helices with opposite chirality for each type are distributed in adjacent layers. Compound 6 exhibiting a unique simultaneous threading fashion of adjacent polymeric motifs gives the novel (2D → 3D) polythreaded array where coordinated NO3− anions act as the dangling ligands. Compound 7 is a 6-connected 3D self-penetrating network where right- and left-handed single-stranded helical chains (AR and AL) and interlaced triple-stranded helices (BR and BL) coexist. The luminescence properties of compounds 1–7 were also measured and discussed.

Two 2D isostructural organic–inorganic hybrid solid materials based on transition metal mono-substituted Keggin polyoxotungstate with an antenna molecule were synthesized under hydrothermal conditions. Compound 2 with the substituted Co(II) exhibits good photocatalytic activity in the degradation of rhodamine-B (RB) under visible light irradiation.

A unique cationic metal–organic framework was synthesized by connecting the neutral rod-shaped secondary building unit with a cationic dicarboxylate ligand. This framework showed a rare snub square tessellation pattern by the periodic tiling of triangular and square nanotubes. The charge- and size-dependent ion-exchange of anion dyes was investigated.