Peer-Reviewed Journal Details
Mandatory Fields
Song BQ;Yang QY;Wang SQ;Vandichel M;Kumar A;Crowley C;Kumar N;Deng CH;GasconPerez V;Lusi M;Wu H;Zhou W;Zaworotko MJ;
Journal of the American Chemical Society
Reversible Switching between Nonporous and Porous Phases of a New SIFSIX Coordination Network Induced by a Flexible Linker Ligand.
Optional Fields
Closed-to-open structural transformations in flexible coordination networks are of potential utility in gas storage and separation. Herein, we report the first example of a flexible 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 (1) and several porous (, 1, 2, and 3) phases triggered by exposure to N2, CO2, or H2O. In addition, heating 1 to 433 K resulted in irreversible transformation to a closed polymorph, 2. Single-crystal X-ray diffraction studies revealed that the phase transformations are enabled by rotation and geometrical contortion of L. Density functional theory calculations indicated that L exhibits a low barrier to rotation (as low as 8 kJmol-1) and a rather flat energy surface. In situ neutron powder diffraction studies provided further insight into these sorbate-induced phase changes. SIFSIX-23-Cu combines stability in water for over a year, high CO2 uptake (ca. 216 cm3/g at 195 K), and good thermal stability.
Grant Details