In Situ Single-Crystal Diffraction Studies of the Structural Transition of Metal−Organic Framework Copper 5-Sulfoisophthalate, Cu-SIP-3

Abstract

The flexibility of the metal-organic framework Cu(2)(OH)(C(8)H(3)O(7)S)(H(2)O) x 2 H(2)O (Cu-SIP-3) toward reversible single-crystal to single-crystal transformations is demonstrated using in situ diffraction methods at variable temperature. At temperatures below a dehydration-induced phase transition (T < 370 K) the structure is confirmed as being hydrated. In the temperature range where the transition takes place (370 K < T < 405 K) no discrete, sharp Bragg peaks can be seen in the single-crystal X-ray diffraction pattern, indicating significant loss of long-range order. At temperatures higher than 405 K, the Bragg peaks return and the structure can be refined as dehydrated Cu-SIP-3. The loss of guest water molecules can be followed at temperatures below the phase transition giving insight into the mechanism of the dehydration. Addition of nitric oxide gas to the material above the gating opening pressure of 275 mbar also leads to loss of Bragg scattering in the diffraction pattern.

Crystal structure of tetrakis(μ-2-chlorobenzoato-O:O′)-bis(dimethylformamid)dicopper(II), Cu2(C3H7NO)2(C7H4ClO2)4

“…Since the first report of the crystal structure of copper(II) acetate monohydrate [Cu 2 (MeCO 2 ) 4 [2][3][4] wherethe Rrepresents avariety of small andbulky organicgroups [1][2][3][4][5][6][7][8]. Thet itle crystal structure consists of molecules with two Cu atomsl inked by four cbag roups in af ashion similar to that of [Cu 2 (Indo) 4 (DMF) 2 ] × 1.6DMF [3] and the dinuclear structure of [Cu 2 (CH 3 COO) 4 (H 2 O) 2 ] [9][10][11].…”

Chemical Crystallography at the Advanced Light Source

“…On rare occasions, this desolvation of the crystal can cause a structural rearrangement of the framework, for example Cu-SIP-3 (Cu2(OH)(sip)(H2O), sip = 5-sulfidoisophthalate) [66]. The full frameworks before and after dehydration are shown in Figure 10.…”

“…4 (H 2 O) 2 ] cluster found in the re-hydrated crystal of Cu-sip -3. Generated using data from [66].…”

Some Difficult Challenges for the Synthesis of Nanoporous Materials

“…Designing and controlling materials to show such transformations, and harnessing any interesting properties that occur, is a significant challenge. Recent progress includes taking more account of the various strengths of bonds in a ligand, using strong bonds to hold the structure together while allowing reactions to happen at the weaker bonds in a structure [40,41]. Such a strategy led to the development of material that only adsorbed one particular gas (nitric oxide) and none of the other common gases tested, illustrating the promise that this strategy holds (Fig.…”