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1 Electronic Sulementary Material (ESI) for ChemComm. This journal is The Royal Society of Chemistry 2016 Suorting Information Photoswitching adsortion selectivity in a diarylethene-azobenzene MOF Cong Bin Fan, a Zhi Qiang Liu, c Le Le Gong, b An Min Zheng, c * Le Zhang, b Chang Sheng Yan, b Hui Qiong, Wu, b Xue Feng Feng b and Feng Luo b * (1) The synthesis of ECUT-30. A solvethermal reaction among Zn(NO 3 ) 2.6H 2 O, L and H 2 AzDC in a ratio of 1:1:1 in a ure DMF solution (5mL), was heated at 110 C for 2 days, and then cooled to room temerature at 3 C/h. Subseuently, block brickred crystals were obtained in 86% yield based on Zn. Element analysis (%) for ECUT-30: calc. C (60.11), H (3.04), N(7.94); ex. C (59.82), H (2.76), N(8.14). (2) Materials and General Methods. The reagents excet that L ligands are synthesized in our lab 8b and solvents were commercially available (Alfa) and were used without further urification. X-ray owder diffraction were collected by a Bruker AXS D8 Discover owder diffractometer at 40 kv, 40 ma for Cu Kα, (λ = Å). The simulated owder atterns were calculated by Mercury 1.4. Thermogravimetric analysis (TGA) was erformed by a TGA Q500 thermal analysis system and all the exeriment were erformed under a N 2 atmoshere from C at a rate of 5 C/min. Data were analyzed using the TA Universal Analysis software ackage. UV-Vis was measured by a Hitachi UV-365 sectrohotometer. The gas sortion isotherms were collected on Belsor-max. The as-synthesized samle (weight of about 80 mg) was degassed in the samle tube and dried for 24 h at 130 C rior to measurements. Ultrahigh-urity-grade (> %) N 2, CO 2, C 2 H 4 and C 2 H 2 gases were used in this adsortion measurement. To maintain the exerimental temeratures mixed liuid nitrogen and acetone (195K), and temerature-rogrammed water bath (273 K) were used, resectively. And 293 K was controlled by close air-condition system and traced by thermometer. Moreover, before degassing, the fresh samles were emerged in methanol for three days with changing fresh CH 3 OH three times a day. For hotoswitching exeriments, the UV lam-house is fixed around the samle tube with the distance more than 40 cm to eliminate ossible temerature effect on CO 2 adsortion resulted from UV. And this is confirmed by thermometer. Furthermore, all the hoto-switching exeriments are tested based on the same samles without any shake under the same conditions of aaratus arameter. (3) X-ray Crystallograhy. Unit cell measurements and intensity data were collected at 296 K on a Bruker-AXS SMART Breeze CCD diffractometer using grahite monochromated MoKα radiation (λ= Å). The data reduction included a correction for Lorentz and olarization effects, with an alied multi-scan absortion correction (SADABS). The crystal structure was solved and refined using the SHELXTL rogram suite. Direct methods yielded all nonhydrogen atoms, which were refined with anisotroic thermal arameters. All hydrogen atom ositions were calculated geometrically and were riding on their resective atoms. CCDC number is The data can be obtained free of charge (htt://

2 Comound ECUT-30 Emirical formula C 53 H 32 F 6 N 6 O 8 S 2 Zn 2 Formula weight Sace grou Monoclinic, C2/c Temerature 296(2)K a (9)Å b (9) Å c (6) Å β (2)º Volume (4)Å 3 Z 4 Crystal size cm Calculated density Mg/m 3 F(000) 2408 Theta range for data collection 2.26º-27.27º Comleteness to theta 100% Goodness-of-fit R indices (all data) R1=0.0453, wr2= (4) Modules and simulation. The structure of ECUT-30a was otimized at PW91/DNP theoretical level as imlemented in the DMol3 ackage to obtain the accurate atom osition of MOF material. In the structure otimization, the cell arameters of the MOF material were maintained as exerimentally observed. The obtained atom coordinates and according atomic charges were used for the further Monte Carlo (MC) simulation. In this work, three kinds of gas molecules, carbon dioxide (CO 2 ), ethylene (C 2 H 4 ) and acetylene (C 2 H 2 ), were investigated by the MC simulation, and their locations inside the framework will be discussed. In the MC simulation, MOF suer cell was used and the loading number were fixed at 49, 81 and 89 molecules for CO 2, C 2 H 4 and C 2 H 2, according to the exerimental adsortion isotherms at 100 kpa. The MOF structures were considered rigid and fixed at above otimized ositions. Periodic boundary conditions were alied in all three dimensions. The charges were added for each atom in the MOF unit cell for the simulations. The TraPPE and TraPPE-UA otential were used to describe CO 2 and C 2 H 4, while the otential arameters for C 2 H 2 were taken from the work of Fischer et al. It s confirmed that these force fields can well consist of the Van der Waals (vdw) and electrostatic interactions of host-guest and guest-guest in the adsorbed systems. The vdw interactions were described by a Lennard-Jones (LJ) otential truncated and shifted at a cutoff distance of 12.8 Å. The LJ arameters for framework atoms of the MOF were taken from the general DREIDING force field excet for Zn metal atoms, which corresond to UFF. All the LJ cross-interaction arameters were determined by the Lorentz-Berthelot mixing rules. The long-range electrostatic interactions were handled using the Ewald summation techniue. The MC simulations roceeded for cycles of euilibration followed by of roduction, the structure was rinted every 100 cycles after euilibration to analyze the density mas (a owerful analysis tool that could show the referred ositions of the sorbates in the MOF) and radial distribution functions (a useful uantity for reresenting the local structure of gas molecules adsorbed in MOF framework). The MC simulations were erformed by using RASPA2.0 simulation ackage, and the following density mas were made using VTK software. (5) Fitting of ure comonent isotherms.

3 The ure comonent isotherm data for C 2 H 2, C 2 H 4, and CO 2 were fitted with the dual-site Langmuir- Freundlich isotherm model A, sat ba 1 b A A A B, sat bb 1 b B B B (1) with T-deendent arameters b A, and b B b A b A0 EA EB ex ; bb bb0 ex RT RT (2) (6) Isosteric heat of adsortion. The binding energy of C 2 H 2, C 2 H 4, and CO 2 is reflected in the isosteric heat of adsortion, Q st, defined as Q st 2 ln RT T (3) (7) IAST calculations of adsortion selectivities. We consider the searation of binary mixtures. The adsortion selectivity for C 2 H 2 /CO 2, C 2 H 4 /CO 2, and C 2 H 2 /C 2 H 4 searation is defined by S ads (4) 1, and 2 are the molar loadings in the adsorbed hase in euilibrium with the bulk gas hase with artial ressures 1, and 2. Fig. S1 The TG lot of as-synthesized samles.

4 Fig. S2 The PXRD atterns simulated from single crystal data, of the as-synthesized samles after drying naturally, of the as-synthesized samles after activation at 130 C under vacuum, of the activated samles after UV-irradiation about 1min. Fig. S3 C 2 H 2 /C 2 H 4 /CO 2 adsortion isotherms of ECUT-30a at 293K/273K, resectively: adsortion (solid symbols) and desortion (oen symbols).

5 Fig. S4 The isosteric heats of adsortion of CO 2, C 2 H 4 and C 2 H 2, resectively. Fig. S5 Radial distribution functions for CO 2, C 2 H 4 and C 2 H 2 in MOF material. Fig. S6 UV-Vis sectrum for ECUT-30a under UV/red or ambient/black.