Structural Manipulation of a Zirconocene-Based Porous Coordination Cage Using External and Host–Guest Stimuli

Xiao, Zhifeng; Drake, Hannah F.; Rezenom, Yohannes H.; Cai, Peiyu; Zhou, Hong-Cai

doi:10.1002/sstr.202100133

Title: Structural Manipulation of a Zirconocene-Based Porous Coordination Cage Using External and Host–Guest Stimuli

Journal Article · Wed Nov 24 00:00:00 EST 2021 · Small Structures

DOI:https://doi.org/10.1002/sstr.202100133· OSTI ID:1976412

^[1];

^[1]; Cai, Peiyu ^[1];

^[1]

Texas A & M University, College Station, TX (United States)

Porous coordination cages (PCCs) constructed from a zirconocene-based cluster have drawn great attention for their high stability and structural tunability. These features have enabled these cages to be utilized for a wide array of applications. Here this work demonstrates the structural flexibility and stimulus-responsive features of two interconvertible zirconocene-based PCCs. The subjects, PCC-20c (capsular) and PCC-20t (tetrahedral), are constructed from the same cluster and ligand but exhibit different shapes and properties. In the synthetic study of the cages, it is found that higher temperatures of synthesis yield PCC-20c in several different crystalline phases while lower temperatures of synthesis yield pure phase PCC-20t. Thermodynamic studies on the interconversion of the two cages show that the conversion from PCC-20t into PCC-20c is an entropically driven process and can be largely affected by the solvent environment. Additionally, the process of PCC-20t/c conversion can be mediated by the counter anions and light irradiation as evidenced by the change in equilibrium constants under these influences. The current studies are conducted to decipher how the PCC-20t/c phase can be controllably synthesized, interconverted, and their properties can be modified under the use of external stimuli: heat, light, and guest molecules.

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Research Organization:: Pennsylvania State Univ., University Park, PA (United States); Texas A & M Univ., College Station, TX (United States)

Sponsoring Organization:: USDOE Office of Fossil Energy (FE); Robert A. Welch Foundation; Qatar National Research Fund

Grant/Contract Number:: FE0026825; AC02-05CH11231; A-0030; NPRP9-377-1-080

OSTI ID:: 1976412

Journal Information:: Small Structures, Vol. 3, Issue 5; ISSN 2688-4062

Publisher:: WileyCopyright Statement

Country of Publication:: United States

Language:: English

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Title: Structural Manipulation of a Zirconocene-Based Porous Coordination Cage Using External and Host–Guest Stimuli

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