Structural diversity and modification in Ni(ii) coordination polymers: a peculiar phenomenon of reversible structural transformation between a 1D ladder and 2D layer

The coordination of 5-tert-IPA²⁻ ligands, the relaxation of the interdigitated 2D net and the breaking and connecting of the bis-pyridyl-bis-amide ligand demonstrate the peculiar reversible structural transformation between a 1D ladder and 2D layer.

Open and closed forms of the interpenetrated [Cu2(Tae)(Bpa)2](NO3)2·nH2O: magnetic properties and high pressure CO2/CH4 gas sorption

Two closed and one open structural forms of the interpenetrated [Cu₂(Tae)(Bpa)₂](NO₃)₂·nH₂O (H₂Tae = 1,1,2,2-tetraacetylethane, Bpa = 1,2-bis(4-pyridyl)ethane) cationic coordination polymer have been synthesized. Three crystallographically related interpenetrated "ths" cationic nets encapsulate water molecules and nitrate anions giving rise to the closed structural forms of [Cu₂(Tae)(Bpa)₂](NO₃)₂·nH₂O. Depending on the location of water molecules and nitrate groups, two different closed forms with 5.5 and 3.6 crystallization water molecules have been obtained. The thermal activation of the closed structures gives rise to a 29% expansion of the unit cell. This closed to open transformation is reversible, and is triggered by the loss or uptake of solvent. The high pressure gas adsorption experiments show similar selectivity values towards CO₂ for CO₂/CH₄ mixtures to that showed by some metal organic frameworks without unsaturated metal sites, and isosteric heats for CO₂ adsorption similar to that for the HKUST-1 compound.

Water-induced phase transformation of a CuII coordination framework with pyridine-2,5-dicarboxylate and di-2-pyridyl ketone: synchrotron radiation analysis

Water-induced reversible phase transformation in the Cu^II–PDC–(py)₂C(OH)₂ system.

CuII–PDC-bpe frameworks (PDC = 2,5-pyridinedicarboxylate, bpe = 1,2-di(4-pyridyl)ethylene): mapping of herringbone-type structures

This work explores new metal–ligand combinations to produce flexible SCFs based on 3-c herringbone layers. The work analyses this type of layers, and provides correlation tools for the structural parameters.