Crystal Flexibility Design through Local and Global Motility Cooperation.

Area of Science:

• Materials Science
• Supramolecular Chemistry
• Chemical Engineering

Background:

• Conventional soft porous crystals lack cooperative properties achievable with integrated local mobility.
• Designing porous materials with tunable structures and functions remains a significant challenge.

Purpose of the Study:

• To develop a flexible porous crystal framework by integrating substituent moieties and a porous coordination polymer (PCP) framework.
• To investigate the structural transitions and guest-free structures of the resulting PCPs under different activation conditions.
• To explore the material's ability to discriminate C6 alkane isomers based on flexible gate-opening behaviors.

Main Methods:

• A design strategy integrating substituent moieties with a flexible porous crystal framework using intra-framework π-π interactions.
• Characterization of framework structural transitions and guest-free structures.
• Evaluation of C6 alkane isomer discrimination based on gate-opening behaviors.

Main Results:

• The integrated design facilitates framework structural transitions.
• The PCPs exhibit distinct guest-free structures dependent on activation conditions.
• The flexible material successfully discriminates C6 alkane isomers via differential gate-opening.

Conclusions:

• The proposed strategy offers a novel approach to designing flexible PCPs with tunable structures and functions.
• The developed PCP shows potential for C6 isomer separation in petroleum refining.
• Ligand designability is key to achieving desired structural and functional properties in flexible porous materials.