A double-walled triangular metal-organic macrocycle based on a [Cu-2(COO)(4)] square paddle-wheel secondary building unit

A metal-organic macrocycle (MOM), [(Cu-2)(3)L-6(DMF)(2)(H2O)(4)], was prepared using a long and "pseudo-rigid" dicarboxylic acid, 1,4-bis(3-carboxylphenylethynyl) benzene (H2L), with some rotational flexibility, where the MOM has a double-walled triangular geometry with three Cu paddle-wheel secondary building units (SBUs) doubly connected by the ligands in a cis-conformation.close8

A two-fold interpenetrated (3,6)-connected metal-organic framework with rutile topology showing a large solvent cavity

A two-fold interpenetrated metal-organic framework (MOF), [(Zn(4)O)(2)L(4)(DMF)(2)(H(2)O)(3)], was prepared using the tritopic ligand 4,4',4 ''-[1,3,5-benzenetriyltris(carbonylimino)]trisbenzoic acid (H(3)L) and zinc nitrate. The MOF, based on the hexatopic tetranuclear Zn(4)O(COO)(6) secondary building unit, has a (3,6)-connected network with an rtl topology and a large solvent cavity.close302

A microporous metal-organic framework constructed from a 1D column made of linear trinuclear manganese secondary building units

A metal-organic framework (MOF) was prepared based on a 1D column made of a linear trinuclear manganese cluster as a secondary building unit (SBU), where the SBU is connected to two adjacent SBUs by carboxylates to form a 1D column and the column is further connected to four adjacent 1D columns via the SBUs to form a microporous MOF of pcu network topology.close7

Entropically driven self-assembly of a strained hexanuclear indium metal-organic macrocycle and its behavior in solution

The self-assembly of a polyprotic pentadentate ligand, N-cyclopentanoylaminobenzoylhydrazide (H4L4), and an In(III) nitrate hydrate in methanol led to a strained hexanuclear indium metal-organic macrocycle (In-MOM), [In(III)(6)(H2L4)(6)(NO3)(x)(solvent)(6-x)](NO3)(6-x) (where, the solvent is either methanol or a water molecule and x is the number of the nitrate anions ligated). The ligand in the doubly deprotonated state serves as an unsymmetric linear ditopic donor and the alternating indium ions in two different chelation modes serve as two different bent ditopic metal acceptors, which led to a D-3-symmetric hexanuclear In-MOM. Although the hexanuclear In-MOM is enthalpically unfavorable because of the ring strain, the combination of the soft coordination characteristic of the indium ion and the slight ligand deformation from the conjugated planar conformation allows the formation of the entropically favored hexanuclear In-MOM rather than the enthalpically favored octanuclear In-MOM. While the hexanuclear In-MOM is stable in acetonitrile, it partially dissociates into its components in dimethylsulfoxide, and then slowly reaches a new equilibrium state with several different indium species yet to be identified in addition to the free ligand.close4

Single crystalline hollow metal-organic frameworks: a metal-organic polyhedron single crystal as a sacrificial template

Single crystalline hollow metal-organic frameworks (MOFs) with cavity dimensions on the order of several micrometers and hundreds of micrometers were prepared using a metal-organic polyhedron single crystal as a sacrificial hard template. The hollow nature of the MOF crystal was confirmed by scanning electron microscopy of the crystal sliced using a focused ion beam.open2

An unprecedented twofold interpenetrated layered metal-organic framework with a MoS2-H topology

An unprecedented twofold interpenetrated layered metal-organic framework with a two-dimensional 3,6-connected net topology has been prepared using a tricarboxylic acid as a 3-connected node and a Zn4O(COO)(6) cluster as a 6-connected node, where the ligand flexibility and the combination of pi-pi stacking and hydrogen bonding interactions render the 6-connected node into a topological trigonal prismatic node.close10

Crystal-to-Crystal Transformations of a Series of Isostructural Metal-Organic Frameworks with Different Sizes of Ligated Solvent Molecules

Isostructural 3D metal-organic frameworks (MOFs) [Zn-2(BTC)(NO3)S-3] [where BTC = 1,3,5-benzenetricarboxylate; S = EtOH (1), DMF (2), DMA (3), or DEF (4)] of a 3-connected srs net topology have been prepared in the presence of serine as a template. The MOFs show different framework stabilities depending on the sizes of the ligated solvent molecules and undergo a crystal-to-crystal transformation at ambient conditions into a ID chain structure either directly or via different types of intermediates depending on the ligated solvent molecules and the sample handling conditions. A single crystal of the MOF with the ligated DMF molecules, [Zn-2(BTC)(NO3)(DMF)(3)] (2), is stable in Mg-II- and Co-II-DMF solutions; however, it transforms into a sing,le particle-like microcrystalline aggregate of Cu-HKUST-1 in a Cu-II-DMF solution.close