Themed collection Structural Design of Coordination Polymers

Welcome to this CrystEngComm themed issue on the structural design of coordination polymers.

This work highlights the current strategies used to activate metal–organic framework materials.

Mixed linkers based frameworks are structurally or topologically versatile and show excellent gas storage and separation properties. Multiple functionalities can be assembled in a single framework system and properties such as molecular sensing, catalysis, magnetism etc. can be tuned to a greater extent.

Coordination chemistry around the tectonic units of MOFs and additional interplay of solvent and anionic species rule out structure prediction.

Reactions at the metal centers of PCPs by other guest molecules, in a single-crystal-to-single-crystal mode, can offer ways to modify the coordination space for directing multiple small molecules cooperatively and enhance MOFs' functionalities.

This article highlights the recent advances and challenges on the structures and properties of W–Cu–S-based cluster polymers.

A series of coordination polymers incorporating lanthanide centres, [Au(CN)₂]⁻ units and the highly anisotropic building block bis(benzimidazole)pyridine have been prepared. Setting a new benchmark for high birefringence in coordination polymers, these materials are also highly emissive.

A rare example of an in situ linker generation and the formation of two MOFs (IFP-9 and -10) are synthesized under solvothermal condition. Gas-sorption behavior of both materials showed the hysteretic isotherms, indicating the flexible MOFs.

The formation of copper(I) coordination polymers featuring a 1D staircase and a 2D polycyclohexane framework is controlled by steric factors.

The coupled chemical and structural insights provided by combining PDF and IR measurements resolve the influence of different types of guests in a nanoporous Prussian blue analogue.

The metal–organic framework CPO-27-Ni can act as a releasing agent of multiple non-conventional anticancer drugs, namely, RAPTA-C and NO.

Ti-MIL125-NH₂ is post-synthetically modified utilising a novel and mild amide synthesis.

Highly luminescent dense frameworks ³_∞[Sr_1−xEu_xIm₂], x = 0–1, were used for in situ growth on nanoporous AAO membranes. Initial growth inside the AAO channels can be observed before a closed layer is formed.

A series of narrowly dispersed nano- and microsized CPAs has been prepared from a (porphyrin)Mn(III) biscarboxylic acid and Co(OAc)₂.

Organic links of varied structure metrics and functionalities connect with Cu₂(COO)₄ clusters to afford layered metal–organic frameworks incorporated with polyoxometalates.

Combining electron diffraction tomography and high resolution transmission electron microscopy for structure determinations of metal organic frameworks.

A linear coordination polymer transformed to a sheet by the loss of coordinated DMF, which rearranged to a ladder polymer when the desolvated single crystals were ground to powder.

An unsymmetrical tricarboxylate ligand with linking alkyne moiety has been used to construct a highly porous metal–organic framework with agw topology, exhibiting a high BET surface area of 3337.0 m² g⁻¹, a large capacity of CO₂ (21.2 mmol g⁻¹ at 298 K and 20 bar) and a good H₂ adsorption (5.8 wt% at 77 K and 20 bar).

In spite of interpenetration, the novel pcu-a topology cobalt(II) MOF-5-type metal organic framework exhibits a highly accessible porous structure.

A 3D 2p–3d heterometallic metal–organic framework based on anovel cubic-like Co₈L₁₂ cages has been synthesized and investigated.

Porous Fe₂O₃ nanocubes composed of ultrafine Fe₂O₃ nanoparticles have been derived from Fe-containing metal–organic frameworks (MOFs), showing promising electrochemical lithium storage properties.

A novel mesoporous lanthanide metal–organic framework with hey topology was constructed from a dendritic hexacarboxylate, and the permanent porosity was established by gas sorption isotherms.

We prepared two new Zn–Ni MOFs based on either triazolate or diaminotriazolate in which the functional ligands play a major role for both the photoluminescent and the gas sorption properties.

A fast synthesis approach toward sub-60 nm sized MOF nanoparticles was developed by employing auxiliary additives.

This communication explores the structural consequences of N9-propyladenine N¹-oxide by varying five different counteranions in silver salts.

Two rare indium-based porous metal–metalloporphyrin frameworks with pts topology were constructed based upon two custom-designed porphyrin ligands and they exhibited interesting CO₂ adsorption properties.

ZIF-8 thin films and patterns were obtained through the solvent-free reaction of deposited ZnO films with melted 2-methylimidazole.

We report the first example of mixed oxalato/oxamato-based chiral 3D MOP with an open-framework structure built up from double helical Mn^IICu^II ferrimagnetic chains.

The work presents the incorporation of two nitro-functionalized biphenyldicarboxylic acid ligands into Zn(II)-paddlewheel MOFs and a Zn(II)-based 2D coordination polymer.

A new molybdenum diphosphonate network structure has been prepared and structurally characterised. It shows reversible dehydration, which occurs with a structural change, and the dehydrated material is able to adsorb methanol but not ethanol.

A series of tetranuclear nickel(II) complexes [Ni^II₄L¹₄(H₂O)₄] (1), [Ni^II₄L²₄(MeOH)₃(H₂O)] (2), [Ni^II₄L²₄(H₂O)₄] (3), [Ni^II₄L³₄(MeOH)₄] (4), [Ni^II₄L⁴₄(MeOH)₄] (5) have been synthesized by employing alkoxo–phenoxo ligands and magnetostructural analysis has been performed.

A series of photoluminescent fluorinated lanthanide-organic frameworks, [Ln(H₃tftp)(H₂O)], has been successfully prepared using novel H₆tftp and Ln³⁺ cations.

Four distinct iptycene-containing metal–organic frameworks (MOFs) were synthesized and characterized using two new organic ligands.

A remarkable single crystal-to-single crystal transformation and an unusual mode of interpenetration are reported as part of an investigation into coordination polymers formed when Cu(II) centres are linked by singly-charged dicarboxylate ligands.

Post-synthetic modification of CPO-27(Mg) (Mg-MOF-74) with Ni²⁺ gives cation exchange and materials with high permanent porosity upon thermal activation.

The metal–organic gels were found to contain intertwined fibrous structures which are stabilized by weak interactions such as coordination, hydrogen bonding and π–π interactions and also exhibit good self sustainability, dye and gas absorption properties.

A series of zinc-based fluorescence active MOFs (or FAMs) built on prototypical paddle-wheel secondary building unit (SBU) act as effective sensors for the vapor phase detection of electron-deficient and electron-rich aromatics as well as nitroaliphatics.

The utility of the supramolecular synthon concept in understanding the aggregation mechanism in flexible polyaminocarboxylate based CPs is illustrated.

Temperature induced structural variation was demonstrated in two new cadmium(II) coordination polymers, {[Cd(BTG)(bpy)(H₂O)]·0.5glycol·H₂O}_n (1) and {[Cd₆(BTB)₄(byp)_4.5(glycol)]·9H₂O}_n (2).

Instead of involving chiral ligands, chiral solvents, and chiral promoters, a “host–guest key–lock” model is demonstrated with four simultaneous pairs of C–H⋯F, C–H⋯O, and C–H⋯N hydrogen-bondings to generate a chiral coordination polymer.

Four Ag(I)-MOFs with diverse pore shape have been assembled by coordination bonds, π–π interactions and silver–oxygen interactions via different counterions.

Three new metal–organic frameworks (MOFs) have been synthesised from alkali earth metal ions of increasing ionic radii (Mg, Ca and Sr) and 2,2′-dihydroxybiphenyl-4,4′-dicarboxylic acid (H₄diol).

A stable 3D Magnesium MOF resembles the topology of MIL-53. It can selectively adsorb CO₂ over N₂ after solvent removal.

Seven Cd^II coordination polymers with a pair of 5-halonicotinic acids are presented, which display diverse polymeric structures to reveal the significant solvent and ligand halogen-substituting effect.

A change from a 2-D to a 3-D MOF structure, which both incorporate structurally similar metal nodes, is engineered by incorporating additional steric bulk onto the ligand backbone.

Out of several ionic salts, potassium halides, CsCl and CsNO₃, only CsCl behaves differently in an assembly formation reaction, retaining the CsCl bond intact in the product.

Phase evolution and importance of anion in the synthesis of MIL-88B and why chloride is needed are reported.

MOF-5 analogs have been synthesized with ligands combining a pyrazolate and carboxylate functionality. These porous Metal–Azolate–Carboxylate (MAC) frameworks have the same cubic pcu-a topology and {M₄(μ₄-O)} nodes (M = Co, Zn) as IRMOFs. Small pore apertures and narrow pores yield a H₂ and CO₂ uptake higher than MOF-5.

Self-assembly structures of AgCPs strongly depend on conformational restriction and steric bulk of oxa-bowl ligands and counter anions.

Metal–organic frameworks with structures related to the MIL-53 framework have been crystallised for divalent metals and mixtures of metals.

A new amino acid based homochiral MOF has been synthesized and comparisons with its earlier congeners show an exciting structure–property relationship.

Choice of metal and hence dimensionality of coordination polymers influences morphology of rapidly precipitated particles.

In a series of 2D (4,4) sheet coordination polymers a dipyridylazacrown ether variable length ligand shows a remarkably consistent adoption of the S-configuration when empty or singly protonated with a water guest, with bridging lengths varying by only 1.3 Å.

Parallel monitoring at the bulk, single crystal and surface level provide unique insight into the solvothermal crystallisation, and potential control over the crystal properties, of ZIF-8.

An N-bridged tripodal urea receptor (L₁) in combination with 18-crown-6-ether (L_C) has been structurally authenticated to self-assemble into an integrated 1D coordination polymer in the presence of potassium carbonate (K₂CO₃).

By using alkali metal ions as structure-directing agents, four diverse superhydrophilic coordination polymers with perhalogenated terephthalates were prepared, which will be converted to new complexes via recrystallizating in water.

Two new CPs based on Sr²⁺ and Cd²⁺ have been synthesized using a new tricarboxylic acid ligand with 3D and 1D structures, and their photoluminescence behavior has been studied.

Attractive interactions between methyl groups of imidazolate linkers (visualized here through a Non covalent interaction analysis) play an important role in the energy landscape of zeolitic imidazolate frameworks.

Four metal–organic coordination polymers based on 5-hydroxyisophthalic acid and various N-containing ligands were synthesized and characterized.

Reactions of Co(II) or Ni(II) salts with 5-(pyridin-4-yl)isophthalic acid in the absence or presence of auxiliary N-donor ligands afforded ten entangled coordination polymers.

Eight MOFs constructed from a synthetically-accessible tetrahedral ligand were structurally and topologically analyzed.

The monocarboxylic acid (so called modulator) behaves as a structure directing agent during the synthesis of MOFs containing Zr₆O₈ cluster and decreases the connectivity of the SBU from 12 to 8 and even to 6. Hence three different porous MOFs could be synthesised.

Three cobalt(II) frameworks with different structures and colours were obtained by tuning pH values of reaction solution.

Indium MOFs as the catalyst in the cyanosilylation of carbonyl compounds following a two-component system mechanism.

In the two diamond networks, one has a rare reversible phase transition between a racemic-twinning chiral and a non-twinning noncentrosymmetric structure.

Several novel MOFs were computationally designed which show a high performance for aniline recovery from aqueous solution.