Supporting Online Material for

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1 Supporting Online Material for A Chromium Terephthalate Based Solid with Unusually Large Pore Volumes and Surface Area G. Férey, C. Mellot-Draznieks, C. Serre,* F. Millange, J. Dutour, S. Surblé, I. Margiolaki *To whom correspondence should be addressed. serre@chimie.uvsq.fr This PDF file includes: Published 23 September 2005, Science 309, ppp (2005) DOI: /science Materials and Methods Figs. S1 to S6 Table S1 References and Notes

2 A Chromium Terephthalate-Based Solid with Unusually Large Pore Volumes and Surface Area G. Férey 1,4 C. Mellot-Draznieks, 2 C. Serre, 1 F. Millange, 1 J. Dutour, 1 S. Surblé, 1 I. Margiolaki 3 (1) Institut Lavoisier, UMR CNRS 8637, Université de Versailles St-Quentin en Yvelines, 45 Avenue des Etats- Unis, Versailles Cedex, France (2) Royal Institution, 21, Albemarle Street, W1S 4BS London, Great-Britain (3) ESRF, Grenoble, France (4) Institut universitaire de France Versailles, France Synthesis. Materials and methods. A typical synthesis involves a solution containing chromium(iii) nitrate Cr(NO 3 ) 3.9H 2 O (400 mg, mol (Aldrich, 99%)), mol of fluorhydric acid, 1,4-benzene dicarboxylic acid H 2 BDC (164 mg, mol (Aldrich 99%)) in 4.8 ml H 2 O ( mol); the mixture is introduced in a hydrothermal bomb which is put during 8h in an autoclave held at 220 C. After natural cooling, a significant amount of recristallised terephthalic acid is present. To eliminate most of the carboxylic acid, the mixture is filtered first using a large pore fritted glass filter (n 2); the water and the MIL-101 powder passes through the filter while the free acid stays inside the glass filter. Then, the free terephthalic acid is eliminated and the MIL-101 powder is separated from the solution using a small pores (n 5) paper filter and büchner. The yield of the reaction is 50 % based on chromium. Insertion of Keggin anions. The K 7 PW 11 O 40.nH 2 O salt was prepared according to the method described by Brevard and al (C. Brevard, R. Schimpf, G. Tourne, C. M. Tourne, J. Am. Chem. Soc. 1983, 105, 7059). To a 10 ml of deionised water was added 100 mg of an activated sample of MIL-101 and 200 mg of the K 7 PW 11 O 39.nH 2 O salt under vigourous stirring at room temperature during three hours. The resulting solid, MIL- 101(Keggin) was then filtated and washed three times with a large amount (50 ml) of deionised water and finally dried at room temperature. Chemical analysis. Chemical analyses were performed at the National Center of Analysis of CNRS in Vernaison (France). MIL-101 exhibits a Cr 3 X(H 2 O) 2 O[(O 2 C)-C 6 H 4 -(CO 2 )] 3.nH 2 O (n~25) formula with X=F. As the amount of water is very sensitive to the temperature (see TGA), only the C/Cr and F/Cr ratios are significant. They agree well with the formula deduced from the structure: C/Cr exp =8.2 and F/Cr =0.32 (calc )). Elemental analyses performed on the MIL-101(Keggin) sample indicated W/Cr and C/Cr contents equal to 0.6 and 8.1 on the whole in agreement with the theoretical values (0.6 and 8.0 %, respectively). Surprisingly, only traces of potassium were found for the MIL-101(Keggin)sample. This would be due to a cation exchange between protons from the MIL-101 framework and the potassium ions from the keggin salt. A complete study of this keggin insertion process within MIL-101 is under progress and results will be reported very soon in another journal.

3 Structure Determination. High-resolution Powder X-ray diffraction data was recorded on Station ID31 of the European Synchrotron radiation Source (ESRF), Grenoble, France, from a highly cristallised sample of MIL-101 contained in a 1 mm diameter capillary. Station ID31 receives X-rays from the synchrotron source (which operates with an average energy of 6 GeV and a current beam of typically 200 ma) from an ondulator device. The incident X-ray wavelength was Å. Data collection was performed over the angular range θ, with a step at 90 K using a cryostream (cold nitrogen gas blower). Cubic cell, a=88.9 Å with adequate figures of merit was found. Systematic absences were consistent with the space group F d-3m (n 227). Based on previous results obtained with the porous chromium trimesate MIL-100 and considering that MIL-101 adopts the same cubic symetry (Space group F d-3m (n 227, origin choice n 2) with an increase in the cell parameter (a=88.9 Å instead of 72.9 Å for MIL-100)), it was highly suggested that the structure of MIL-101 was of the same type as MIL Then, considering the chemical ratio (metal/organic ratio=1), a hybrid supertetrahedra (ST) is built in such a way that the four vertices of the ST are occupied by the trimers while the organic linker is located at the six edges of the ST. The connection of the ST is established via vertices to ensure a three-dimensional network of corner-sharing super tetrahedra with the MTN zeotype architecture, where each tetrahedral center (TO 4 ) typical of zeolites is occupied here by one super tetrahedron. The corresponding structure exhibits a giant 706,000 Å 3 cell volume. The simulated pattern of the MTN-type hybrid structure matches the experimental pattern of MIL-101 leading to the direct-space structure solution of the new phase and ensuring a valid model for the structure refinement. The refinement required high quality synchrotron radiation. Finally, the atomic coordinates of the MTN-type model predicted from the simulation was used to perform the Rietveld refinement of the MIL-101 sample synchrotron diffraction pattern. After a pattern matching performed using Fullprof 2 and its Winplotr interface, 3 the structure refinement was initiated using the atomic positions obtained from the simulations. The structure of MIL-101 was first refined using also Fullprof and in a second step, several successive Fourier differences were performed, using the Shelxtl97 program, 4 to locate the missing water molecule atoms present within the pores. Some of the water molecules were found occupying disordered crystallographical sites and partial occupations were applied. Fluorine counter anions present in MIL-101, are probably located in terminal position bounded to chromium atoms. The whole structure of MIL-101 was finally refined using Fullprof. Experimental points were used to adjust the background with a Pseudo-Voigt function to determine the peak profile. Two asymmetry parameters, one overall thermal parameter were also applied during refinements. Distance and angle constraints were used during the refinement especially to refine the terephthalate anion as a rigid body. Despite the large number of parameters (74 independent framework atoms (~170 parameters) in a cell volume of 702,000Å 3 ), the refinement converges toward good R values 5 (R p =8.37 %, R wp =11.4 % and R Bragg =5.63 %). Crystal data and structure refinement parameters are reported in Table S1. The final Rietveld plot is reported on figure S1. The refinement correctly converged towards the general formula Cr 3 F(H 2 O) 3 O[C 6 H 3 -(CO 2 ) 2 ] 3.nH 2 O (n~15) which is in agreement with the chemical analysis. The smaller water content deduced from the structure determination (compared with the TGA results) comes from the use of a very high energy flux of ID-31 which, despite the use of a cryostream, causes a probable loss of free water molecules.

4 Tables and Figures. Table S1 : Crystal data and structure refinement parameters for MIL-101. Cr 3 X(H 2 O) 2 O[(C 6 H 4 )-(CO 2 ) 2 ] 3.nH 2 O Formula X=F,OH; n~15 Molar mass (g mol -1 ) 989 (X=F) System cubic Calculated density (g.cm -3 ) 0.62 Space group Cell parameters Figures of merit Fd-3m (n 227, origin choice n 2) a = Å (1) V= Å 3 (1) M 20 =12 F 20 =90 (0.0024, 93) Synchrotron Radiation (Å) Data collection ( ) Number of independent reflections 2854 Number of independant atoms 108 N. intensity-dependent parameters 271 N. profile parameters 9 R P 8.4 R WP 11.4 R B 5.6 (R1 = Σ( F 0 - F c ) / Σ F o et wr2 =[Σw(F o 2 - F c 2 ) 2 / Σw(F o 2 ) 2 ] 1/2 ) Figure S1: Final Rietveld Plot of MIL-101.

5 Thermal Analysis. A thermal gravimetric analysis study evidenced an interesting stability of MIL-101 (fig. S2). A crystalline sample of MIL-101 was heated from 25 to 600 C in air at a constant rate of 2 C min -1. Two weight-loss steps were observed : the first, corresponding to 40%, occurrs in the range C relates to the loss of guest water molecules (calculated : 40%) ; the second (44 %) is due to the departure of OH/F groups and the decomposition of the framework between 275 and 400 C (calculated: %). It has also to be mentionned that the water content of MIL-101 varies considerably, from 30 % up to 60 %, depending on the presence of coordinated solvent, the temperature in the laboratory, or the rate of humidity... A thermal gravimetric analysis study performed on the MIL-101(Keggin) sample. Two weight-loss steps were observed : the first, corresponding to 27 %, occurs in the range C relates to the loss of free and bound water molecules; the second (~37 %) is due to the departure of OH/F groups and the decomposition of the framework around 350 C (calculated loss: 40%). The residual solids are Cr 2 O 3 for MIL-101 or a mixture of Cr 2 O 3 and WO 3 oxides for MIL-101(Keggin) Weight (%) MIL-101 (Keggin) MIL T( C) Figure S2: TGA of MIL-101 and MIL-101(Keggin) under oxygen atmosphere (2 C/min. heating rate).

6 Nitrogen Sorption Measurements. Experiments were performed on a Micromeritics ASAP 2010 using Nitrogen as the adsorbed gas. Samples were dehydrated under vacuum overnight at 100 C (fig. S3a). Experiments were performed first on the as -synthesised solids. The large surface area of MIL-101 involve the use of small amounts of product (=10-15 mg) for each sorption experiment. To counterbalance errors on weight measurements, experiments were repeated three times and weight losses were calculated based on TGA experiments performed on the same products used for the surface area measurement. This gives Langmuir surface areas within the m 2.g -1 range for MIL-101(assynthesised). The pore volumes vary between 1.5 and 1.9 cm 3.g -1. The discrepancies between the observed values are due to the variable amount of terephthalic acid present as an impurity or present within the pores. The presence of free terephthalic acid within the pores of MIL-101 was expected since other porous vanadium 6,7 or chromium 8 terephthalates contained significant amounts of free carboxylic acid within the pores in their assynthesised forms. To evacuate the free acid, a solvothermal treatment is performed using ethanol (95 % EtOH, 5 % water). In a typical procedure, 100 mg of MIL-101 are dispersed into 20 ml of ethanol and the mixture is introduced in a Teflon liner into a hydrothermal bomb. This latter is held at 100 C (EtOH) during 20h in an autoclave. The resulting solid is cooled down, filtered and washed with the solvent. The solid is finally dried overnight at 150 C under air atmosphere. The resulting solids exhibit higher Langmuir surface areas, typically between 5500 and 6200 m 2.g -1 and pore volumes close to 2.0(2)cm 3.g -1. The langmuir fit is correct (fig. S3b). Again, some discrepancies on the surface area values are present due mostly to the errors on the weight measurements and maybe the purity of the sample. Also, depending on the points chosen for the Langmuir calculation, the calculated surface area can vary more than a few hundred cm 3.g -1 ; we decided therefore to use the points between P/Po=0.05 up to 0.2 which leads to a satisfactory fit. A complete study of the activation process of MIL-101 involving IR temperature spectroscopy is under progress. In a second step, experiments were performed on MIL-101(activated with ethanol) and MIL-101(K 7 PW 11 O 39 ) (fig. S3c). Langmuir surface areas of 5900(300)m 2.g -1 and 3750(250) m 2.g -1 were measured for the two samples, respectively Vads(cm 3.g -1 ) *P/P0 Figure S3a: Typical Nitrogen sorption experiment at 77 K for two samples of MIL-101 (as-synthesised (bottom) and activated using ethanol (top)). The corresponding Langmuir surface areas are 4500 and 5900 m 2.g -1, respectively.

7 Data Fit 1/[V A *(P 0 /P)] Y = A + B*X A= B= R= relative pressure Figure S3b: Langmuir fit for the adsorption isotherm of MIL-101(activated) (1) (2) Vads(cm 3.g -1 ) ,2 0,4 0,6 0,8 1 P/P0 Figure S3c: Nitrogen sorption experiment at 77 K for two samples of MIL-101 (as-synthesised (1) and activated using ethanol (2)).

8 X-Ray Powder diffraction. Laboratory X-Ray diffraction patterns were collected for MIL-101 and MIL-101(K 7 PW 11 O 39 ) on a conventional high resolution (θ 2θ) Siemens D5000 Diffractometer using λ Cu Kα 1, α 2. using 1/0.2 slits, a 0.02 step size and 4 seconds per step (figure S4). MIL-101(Keggin) MIL Theta - Scale Figure S4: X-Ray diffraction pattern (λ=1.5409å) of MIL-101 and MIL-101(Keggin).

9 Infra-Red Spectroscopy. Three thin pellets were first made from KBr and a small amount of MIL-101, the Keggin salt K 7 PW 11 O 39.nH 2 O and the resulting solid MIL-101 (K 7 PW 11 O 39 ). The Infrared spectra (figure S5), performed with a Nicolet- Magma IR550 apparatus, clearly shows the presence of the vibrational bands characteristic of the framework - (O-C-O)- groups around 1550 and 1430 cm -1 confirming the presence of the dicarboxylate within MIL-101 and MIL-101 (K 7 PW 11 O 39 ). Larges bands around 3500 cm -1 and 1630 cm -1 also confirms the presence of a consequent amount of water molecules within these two solids. The characteristics bands of the Keggin anion are also observed within the MIL-101 (K 7 PW 11 O 39 ) solid, indicating the presence of the Keggin salt within this compound. 60 MIL-101(K 7 PW 11 O 39.nH 2 O) MIL-101 transmitance 30 K 7 PW 11 O 39.nH 2 O wave number (cm -1 ) Figure S5: Infra-red spectroscopy of MIL-101, MIL-101(Keggin) and the Keggin salt (K 7 PW 11 O 40.nH 2 O).

10 Solid State NMR. 31 P solid-state MAS spectra were recorded on MIL-101(Keggin) and the keggin salt K 7 PW 11 O 39.nH 2 O (see figure S6) using TegMag APOLLO 200 MHz spectrometer operating at resonance frequency of MHz. Chemical shifts are referenced to NH 4 H 2 PO 4. The samples were spun in a 4 mm zirconia rotor at a spinning rate of 10 khz. 31 P MAS NMR spectra were acquired using a single pulse sequence with a 3 µs π/4 pulse and a 10 s recycle delay. 31 P MAS NMR at 10 khz K 7 PW 11 O 39 : in Mil K 7 PW 11 O 39 : bulk ppm Figure S6: 31P Solid State NMR spectra of MIL-101(K 7 PW 11 O 39 ) and the K 7 PW 11 O 39.nH 2 O salt.

11 References [1] G. Férey, C. Serre, C. Mello-Draznieks, F. Millange, S. Surblé, J. Dutour,R.Margiolaki: Angew. Chem. Int. Ed. 2004, 43, 6297 [2] J. Rodriguez-Carvajal, In "Collected Abstracts of Powder Diffraction Meeting", Toulouse, France 1990, 127. [3] T. Roisnel, J. Rodriguez-Carvajal, In "Abstracts of the 7th European Powder Diffraction Conference", Barcelona, Spain 2000, 71. [4] SHELXL97, University of Göttingen, Germany, [5] P. M. de Wolff, J. Appl. Crystallogr. 1972, 5, 243. [6] K. Barthelet, J. Marrot, D. Riou, G. Férey, Angew. Chem. Int. Ed 2002, 41, 281. [7] K. Barthelet, J. Marrot, G. Férey, D.Riou, Chem. Comm. 2004, 520. [8] C. Serre, F. Millange, C. Thouvenot, M. Nogues, G. Marsolier, D. Louër, G. Férey, J. Am. Chem. Soc. 2002, 124, 13519