Solid state reconstructive phase transition from porous supramolecular network to porous coordination polymer

Area of Science:

• Materials Science
• Supramolecular Chemistry
• Coordination Chemistry

Background:

• Porous supramolecular networks and porous coordination polymers are important functional materials.
• Understanding structural transformations is key to designing new materials with tunable properties.

Purpose of the Study:

• To investigate a unique structural transformation between a porous supramolecular network and a porous coordination polymer.
• To correlate structural changes with alterations in material properties, specifically interpenetration and spin state.

Main Methods:

• Synthesis and characterization of the porous supramolecular network.
• Induction of structural transformation under specific conditions.
• Analysis of the resulting porous coordination polymer using techniques like X-ray diffraction and magnetic susceptibility measurements.

Main Results:

• An exceptional structural transformation from a porous supramolecular network to a porous coordination polymer was achieved.
• The interpenetrating dimensionality changed from 6-fold to 5-fold during the transformation.
• A simultaneous alteration in the spin state of nickel(II) from S = 0 (low-spin) to S = 1 (high-spin) was observed, linked to the formation of Ni-O(carboxylate) bonds.

Conclusions:

• The study demonstrates a novel pathway for structural interconversion between different classes of porous materials.
• The observed spin-state change in nickel(II) highlights the sensitivity of metal centers to the coordination environment within porous frameworks.
• This work provides insights into the design principles for creating advanced porous materials with switchable properties.