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1 SSZ-52, a zeolite with an 18-layer aluminosilicate framework structure related to that of the DeNOx catalyst Cu-SSZ-13 Dan Xie 1,2, Lynne B. McCusker 2 *, Christian Baerlocher 2, Stacey I. Zones 1 *, Wei Wan 3, Xiaodong Zou 3 1 Chevron Energy Technology Company, Richmond, California 94802, USA. 2 Laboratory of Crystallography, ETH Zurich, CH-8093 Zurich, Switzerland. 3 Berzelii Center EXSELENT on Porous Materials, Department of Materials & Environmental Chemistry, Stockholm University, SE Stockholm, Sweden. * corresponding author Supplementary Information Structure directing agent synthesis Figure S1. Sequence of synthesis steps used to produce the structure directing agent (bottom right product) that was used to synthesize the zeolite SSZ-52. S1

2 Diffraction patterns for all 7 models with nine d6r layers Figure S2. Comparison of the simulated XPD patterns for the 7 models (geometry optimized) and the experimental synchrotron XPD pattern. The radiation wavelength is Å. S2

3 Molecular modeling The location and the van der Waals (vdw) interaction energy of the SDA with the SSZ-52 framework were studied by molecular mechanics simulations using the Materials Studio software [ 1 ]. The CVFF forcefield [ 2 ] was selected for the calculation and the most stable locations for the SDA molecules were obtained by simulated annealing. The unit cell was fixed during the calculation. The final interaction energy was normalized per SDA. Initially, one SDA was docked per large cavity, and then the number was increased. The results indicated that the most stable situation was when the large cavity was occupied by two SDA molecules, with their more positive nitrogen ends pointing away from one another towards the two caps of the large cavity. The other two arrangements of the SDA pair, i.e. with the nitrogen ends pointing in the same direction and with the nitrogen ends pointing towards one another and the middle of the cavity, could also be found in local minima of energy space. These two configurations are typically ca. 1 and 6 KJ/mol per SDA higher in energy than the configuration at the global minimum, respectively. The occasional stacking faults create a few additional cavities (see Figure 5): the cha cavity and an extra large cavity (Figures 5c and d), so it was of interest to calculate and compare the interaction energy between the SDA and these cavities as well. The calculation, following the same procedure as described above, clearly indicated that one SDA could fit in the cha cavity and three SDAs in the extra large cavity reasonably well, though less perfectly than two SDAs in the SSZ-52 large cavity. The lowest energy values obtained with the optimum number of SDA(s) in the different cavities are shown in Table S1. Reasoning that the intermediate sized cavities resulting from twinning (Figures 5e and f) might be large enough to include water in addition to the SDA, simple vdw interaction energy calculations were also performed for these configurations. In both cases, the minimum energy was found for six water molecules. The numbers obtained were similar to those found for the other stacking fault cavities, while clearly less favorable than those for two SDAs in the ideal SSZ-52 cavity. Without the water molecules, the energies for these cavities are ca. 20 kj/mol higher. Table S1. Interaction energies for the SDA in different cavities. Lowest interaction energy (per SDA) [kj/mol] One SDA in a cha cavity Two SDAs in an ideal SSZ-52 cavity Three SDAs in an extra large cavity One SDA and six H 2 O in an aft cavity Two SDAs and six H 2 O in a five d6r-layer cavity S3

4 Aluminoslicate ABC-6 zeolites with d6r units Figure S3. Comparison of the structures of the three ABC-6 aluminosilicates that have 3-dimensional 8-ring channel systems and can be built from d6r units only, showing the different cavities formed. In each case, the cavities formed along the long diagonal of the hexagonal unit cell are shown (top: along [001] and bottom along [110]). Stacking sequences: CHA: AABBCC; AFX: AABBAACC; SSZ-52: AABBAABBCCBBCCAACC. S4

5 Transmission Electron Microscopy (TEM) studies The SSZ-52 powder was first ground in a mortar, then dispersed in ethanol by ultrasonic treatment, and finally deposited onto a TEM grid coated with holey carbon film. TEM data were collected on a JEOL JEM-2100F microscope equipped with a field emission gun operated at 200 kv (point resolution 1.9 Å). Selected area electron diffraction (SAED) patterns and high-resolution transmission electron microscopy (HRTEM) images were recorded on a Gatan Ultrascan k 2k CCD camera. Because SSZ-52 was very electron beam sensitive, low dose conditions were applied. 20 images (each with a 4s exposure time) were taken under the same imaging conditions, and then added together in order to enhance the signal-to-noise ratio. The relative shift between the images was determined by cross-correlation and then corrected for using the software QFocus [3]. Simulated electron diffraction patterns were calculated using the software CrystDiff written by Wei Wan [4]. Figure S4. HRTEM images of SSZ-52 (a) from the [121] and (b) [130] zone axes. (c) and (d) are the corresponding symmetry-averaged images from (a) and (b) with the projection symmetry cmm and p2 imposed, respectively. The structure projections from the model are superimposed on the symmetry-averaged images to show the good agreement. S5

6 Figure S5. SAED patterns for SSZ-52 along three different projections. Those shown in (a, b and c) are the experimental patterns and those in (d, e and f) the corresponding simulated ones. The zone axes and indices of some reflections are marked. S6

7 Figure S6. The [100] projection taken from another disordered SSZ-52 crystal. A schematic description of the twinning and stacking disorder is overlaid. The HRTEM image was averaged from 20 HRTEM images taken under identical conditions in order to enhance the signal-to-noise ratio. Formatted: Font: (Default) Times New Roman S7

8 References [1] Materials Studio 6.0, Accelrys, Inc.: San Diego, CA, [2] P. Dauger-Osguthorpe, V.A. Roberts, D.J. Osguthorpe, J. Wolff, M. Genest and A.T. Hagler, Structure and energetics of ligand binding to proteins: E. coli dihydrofolate reductase-trimethoprim, a drug-receptor system. Proteins: Struct., Funct., Genet. 4, (1988). [3] Wei Wan, Sven Hovmöller, Xiaodong Zou, Structure projection reconstruction from through-focus series of high-resolution transmission electron microscopy images. Ultramicroscopy 115 (2012) [4] Wei Wan, (2012) S8