Reversible Switching between Nonporous and Porous Phases of a New SIFSIX Coordination Network Induced by a Flexible Linker Ligand

• DOI: 10.1021/jacs.0c01314
• Publication Date: 2020-03-27T23:56:41Z
• Authors: Bai-Qiao Song; Qing-Yuan Yang; Shi-Qiang Wang; Matthias Vandichel; Amrit Kumar; Clare Crowley; Naveen Kumar; Cheng-Hua Deng; Victoria GasconPerez; Matteo Lusi; Hui Wu; Wei Zhou; Michael J. Zaworotko
• Keywords: Linker; Thermal Stability

Closed-to-open structural transformations in flexible coordination networks are of potential utility gas storage and separation. Herein, we report the first example a SiF62–-pillared square grid material, [Cu(SiF6)(L)2]n (L = 1,4-bis(1-imidazolyl)benzene), SIFSIX-23-Cu. SIFSIX-23-Cu exhibits reversible switching between nonporous (β1) several porous (α, γ1, γ2, γ3) phases triggered by exposure to N2, CO2, or H2O. In addition, heating β1 433 K resulted irreversible transformation closed polymorph, β2. Single-crystal X-ray diffraction studies revealed that phase enabled rotation geometrical contortion L. Density functional theory calculations indicated L low barrier (as as 8 kJmol–1) rather flat energy surface. situ neutron powder provided further insight into these sorbate-induced changes. combines stability water for over year, high CO2 uptake (ca. 216 cm3/g at 195 K), good thermal stability.