Supporting Information. Methane Oxidation to Methanol Catalyzed by Cu-Oxo Clusters Stabilized in NU-1000 Metal Organic Framework

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1 Supporting Information Methane Oxidation to Methanol Catalyzed by Cu-Oxo Clusters Stabilized in NU-1000 Metal Organic Framework Takaaki Ikuno, Jian Zheng, Aleksei Vjunov, Maricruz Sanchez-Sanchez, Manuel A. Ortuño, # Dale R. Pahls, # John L. Fulton, Donald M. Camaioni, Zhanyong Li, Debmalya Ray, # B. Layla Mehdi, Nigel D. Browning,, Omar K. Farha,, Joseph T. Hupp, Christopher J. Cramer, # Laura Gagliardi, # and Johannes A. Lercher*,, Department of Chemistry and Catalysis Research Institute, TU München, Lichtenbergstrasse 4, Garching, Germany Institute for Integrated Catalysis, and Fundamental and Computational Science Directorate, Pacific Northwest National Laboratory Richland, Washington 99352, USA #Department of Chemistry, Supercomputing Institute, and Chemical Theory Center, University of Minnesota, Minneapolis, Minnesota 55455, USA Materials Science and Engineering, University of Washington, Seattle, WA 98195, USA Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA Department of Chemistry, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia

2 TABLE OF CONTENTS Chemical structure representation of the Cu precursor used in the synthesis of Cu-NU PXRD characterization of Cu-NU High Angle Annular Dark Field (HAADF) STEM Characterization of Cu-NU The in-operando XAFS experiment setup... 5 Cu + increase during CH 4 loading... 6 Comparison of Cu-NU-1000 at 25 C and activated at 150 C in O In situ EXAFS spectra of Cu-NU-1000 during the activation in O 2 and during the CH 4 loading... 8 k 1, k 2, and k 3 -weighted EXAFS spectra of Cu-NU-1000 and aqueous Cu Cu-EXAFS standard fitting Activated Cu-NU-1000 fitting The stability of NU-1000 and Cu-NU Analysis for remnants of the dmap ligand in Cu-NU Additional EXAFS data for A and A-2node Alternative structures for Cu n -NU-1000 (n = 1 4) Periodic vs cluster calculations Cartesian coordinates S2

3 Chemical structure representation of the Cu precursor used in the synthesis of Cu-NU Figure S1. Chemical structure representation of the used Cu precursor: Bis(dimethylamino-2-propoxy)copper(II), Cu(dmap)2 PXRD characterization of Cu-NU-1000 XRD demonstrates that the characteristic crystallinity of pristine NU-1000 is mainly retained after Cu deposition. The pattern for Cu-NU-1000 shows less intensity of the diffraction peaks at near 2θ = 7 10, which corresponds to a decrease in the coherency of planes with spacing of nm. Figure S2. XRD patterns of Cu-NU-1000 (black) and parent NU-1000 MOF (magenta) S3

4 High Angle Annular Dark Field (HAADF) STEM Characterization of Cu-NU-1000 In the Figure S3, bright linear features are seen in the crystalline NU-1000 MOF structure. Towards the edge of the sample, areas where the crystallinity has been destroyed, these features are also accompanied by larger non-uniform bright features. However, crystalline areas (Figure 2 and Figure S3a) represent the majority of the sample. Figure S3. HAADF images of the crystalline Cu-NU In (a) large areas of crystalline material can be observed with increased intensity due to Cu(OH)2 clusters aligned to the nodal distribution. At the edge of the sample, the crystallinity is destroyed (either in the processing or sample preparation for STEM) and the bright features indicative of clusters appear to be less uniform and on the surface of the structure. (b) Other non-crystalline areas also show the presence of non-uniform features indicating that larger clusters/particles are associated with degradation of the crystalline structure. The major crystalline component of the structure does not show these larger clusters. A detailed assessment of these features will be provided in separate article focused on the STEM characterization of Metal-NU-1000 MOFs. In what follows we provide a preliminary assessment of whether the features are associated with Cu deposited in the NU-1000 in the form of clusters and/or larger particles of Cu(OH)2. In the Z-contrast mode of operation any projected mass increase is seen as an increase in brightness in the image. This means that all of the bright areas In the image are places where the Cu complexes are likely to reside. In Figure S3a, if one looks at the image just above the bright double line feature that goes across the whole grain, then one sees a series of brighter linear features of varying length. Importantly, all these features are aligned in a particular direction. This direction corresponds to the pore direction where the Cu complexes sit. What the image is showing is that Cu complexes are not in every pore, but they do invariably go to the same pore, and where they exist they do appear to cluster into chains. However, at the magnification of the image shown we cannot see the individual nodes and so what is being seen is essentially double the node distance in all cases, ~3.5 nm, (while the length varies, the width is constant). There may well be situations where isolated Cu complexes are in pores that do not turn up as bright in the image (at this magnification an individual Cu complex would not be seen as clearly). This then also explains the double line seen across the whole image this is a case where chains of Cu complexes are in adjacent unit cells. Figure S3b shows an image where the crystallinity of the MOF is less well defined due to effects of the synthesis, the preparation or the electron beam. Here, the Cu is released from the MOF structure and agglomerated on the surface, which can be distinguished from the Cu complexes in crystalline regions of the MOF as the agglomerates are less uniform. This type of behavior has been seen in zeolites individual atoms can be pushed along the channels with the electron beam but they don t cluster. 1 When the beam is moved to an amorphous edge or turned up high enough to amorphize the structure then clustering is observed. The vast majority of the Cu seen in these images is therefore in the crystal pores even though some clusters are seen on the surface. S4

5 The features in the image are consistent with the nodes being bridged by Cu clusters as in the Figure 7. The reason that they look like rods is that the imaging magnification is insufficient to see the individual clusters. This means that the intensity from each feature gets piled on top of one another and as such they appear to be rods. NU-1000 has six c pores per unit cell in which the Zr6O8 nodes can be bridged by a chain of three Cu(OH)2 complexes. In the bright double line running across the whole image there are gaps where the clusters are missing from the pores in some locations. At higher magnification the contrast difference between pores with Cu and pores without decreases such that a clear contrast separation is not obtained. So, to summarize at lower magnification enough contrast is obtained to show that is copper in specific locations (bright features are all the same width) while at higher magnification the structure is seen to be made up of isolated clusters but unfortunately the contrast difference is not high enough to say for sure which sites have copper and which do not. The in-operando XAFS experiment setup XAFS measurements were performed in transmission mode in-operando under catalytic conditions using a multi-sample flow-cell operated at ambient pressure and temperatures up to 250 ºC. Samples are prepared as self-supporting catalyst wafers. The demonstrated design allows XAFS data collection for multiple samples activated or reacting under identical conditions. This approach allows for both direct comparison of the data and increased sample throughput. The reactor is schematically shown in Figure S4. Lecture bottle Gas supply to cell Cell insulation X-ray beam XAFS Flow-cell Figure S4. The experimental setup used for in-operando XAFS data acquisition. S5

6 Cu + increase during CH 4 loading The increase of the Cu + 1s 4p transition intensity is observed during the catalyst loading with methane. Therefore, we have performed XANES linear combination fitting to determine the change of Cu +. Cu2O and Cu(OH)2 are used as respective references. Linear combination fitting (LCF) was performed with ATHENA programs from the ixafs software package. The normalized XANES spectra of the Cu-NU-000 sample was fitted in the range of -20 to 30 ev (8970 to 9023 ev). As shown in Figure S5 and Table S1, the fractions of Cu + in Cu-NU increased by ~9 % (from ~85 to ~76%) upon the material contact with methane. Similar results were obtained by narrowing the fitting range to -11 to -9 ev (8982 to 8984 ev), which only corresponds to the range of 1s 3d transition of Cu +. The curve fitting on Origin software package (ExpDec1) suggests that the Cu + and Cu 2+ species are nearly equilibrated after 160 minutes, because the fraction of Cu 1+ is leveling off at ~24%. Figure S5. (a) The normalized XANES spectra of Cu-NU-1000 during CH4 loading and Cu2O and Cu(OH)2 references. (b) The growth curve of Cu + species during CH4 loading. Table S1. Linear combination fitting results of the spectra measured during CH4 loading CH4 loading time (min) Cu + fraction and error Cu 2+ fraction and error R-factor ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± S6

7 Comparison of Cu-NU-1000 at 25 C and activated at 150 C in O 2 Figures S6 and S7 show the k 2 -weighted Cu-EXAFS Img[χ(R)] and χ(k) spectra of Cu-NU-1000 at 25 C and at 150 C in flowing O2 after 60 minutes. We see only minor differences of the spectra of Cu-NU-1000 between the 25 ºC and 150 ºC. The slightly smaller peak amplitude in χ(r) spectrum of heated sample is due to dynamic dis. Increased temperature leads to more structural distortions of the Cu-species χ(k). Overall, little change in the Cu-structure was observed during 60 minutes activation in flowing O2 at 150 ºC. Figure S6. A comparison of the k 2 -weighted Cu-EXAFS Img[c(R)] spectra of as-synthesized (black) and activated (magenta) Cu-NU The spectrum of activated sample was scanned after the sample heated at 150 ºC in in oxygen for 60 minutes. Figure S7. A comparison of the k 2 -χ(k) Cu-EXAFS spectra of as-synthesized (black) and activated (magenta) Cu-NU The spectrum of activated sample was scanned after the sample heated at 150 ºC in in oxygen for 60 minutes. S7

8 In situ EXAFS spectra of Cu-NU-1000 during the activation in O 2 and during the CH 4 loading Figure S8 shows the k 2 -weighted Img[χ(R)] spectra of Cu-NU-1000 during O2 activation. No obvious change is found. Figure S9 shows the k 2 -weighted Img[χ(R)] spectra of Cu-NU-1000 during CH4 loading after O2 activation. We hardly see differences of the spectra in CH4 loading except a very weak increase in the magnitude of the Cu- O feature. These results suggest that the main structure of Cu-NU-1000 is not changed. Figure S8. The k 2 -weighted Cu-EXAFS Img[c(R)] spectra of Cu-NU-1000 during activation in oxygen Figure S9. The k 2 -weighted Cu-EXAFS Img[c(R)] spectra of Cu-NU-1000 during methane loading S8

9 k 1, k 2, and k 3 -weighted EXAFS spectra of Cu-NU-1000 and aqueous Cu 2+ Figure S10 shows the k 1 -, k 2 -, and k 3 -weighted Cu-EXAFS Img[χ(R)] spectra of (a) Cu-NU-1000 and (b) aqueous Cu 2+ ions. The Cu-O peak has been scaled so that their amplitudes are approximately equivalent. As the k-weight increases (k 1, k 2, k 3 ) the amplitudes of the features between 2.2 and 3.2 Å increase (Figure S10a). This is indicative of backscattering from a higher-z atom such as Cu and inconsistent with a light element such as O, which should scale with the same as the feature at 1.4 Å. Figure S10. The k 1 -, k 2 -, and k 3 -weighted Cu-EXAFS Img[c(R)] spectra of (a) Cu-NU-1000 and (b) Cu 2+ ions in water S9

10 Cu-EXAFS standard fitting Cu(OH)2 standard is fit to determine the necessary paths and fitting parameters that are then used to analyze the Cu-NU-1000 spectra. Cu-hydroxide single crystal structure 2 is used to calculate scattering paths using FEFF9 software. 3 The fit is shown in Figure S11 and the parameters are reported in Table S2. The same approach is used to with the second standard, Cu2O; 4 the results are shown in Figure S12 and Table S3, respectively. Figure S11. The k 2 -weighted (a) Cu-EXAFS Img[c(R)] and (b) k 2 -χ(k) spectra of Cu(OH)2 (black) and the obtained fit (magenta) are shown. Table S2. The coordination number, average atom distances, and Debye-Waller factors (DWF) determined for the Cu(OH)2 reference by fitting the experimental spectrum with a model derived using FEFF9. The fit is obtained using k-weighting of 2. Other parameters: amplitude reduction factor (amp) = 0.83 ± 0.08, R- factor = , and E0 = -8 ± 0.6. Shell a Coordination Number Distance (Å) DWF Cu-O 1 SS ± ± Cu-O 2 SS ± ± Cu-Cu SS ± ± Cu-Cu2 SS ± ± Cu-O 1 MS ± ± Cu-O 1 MS ± ± ass = single scattering; MS = multiple scattering. S10

11 Figure S12. The k 2 -weighted (a) Cu-EXAFS Img[c(R)] and (b) k 2 -χ(k) spectra of Cu2O (black) and the obtained fit (magenta) are shown. Table S3. The coordination number, average atom distances, as well as Debye-Waller factors (DWF) determined for the Cu2O reference by fitting the experimental spectrum with a model derived using FEFF9. The fit is obtained using k-weighting of 2. Other parameters: amplitude reduction factor (amp) = 0.83 ± 0.07, R-factor = 0.014, and E0 = -9.0 ± 1.4. Shell a Coordination Number Distance (Å) DWF Cu-O 1 SS ± ± Cu-O 2 SS ± ± Cu-Cu1 SS ± ± Cu-Cu2 SS ± ± Cu-Cu3 SS ± ± Cu-O 1 MS ± ± Cu-O 1 MS ± ± ass = single scattering; MS = multiple scattering. The fit is obtained using k-weighting of 2. S11

12 Activated Cu-NU-1000 fitting Cu/NU1000 heated at 150 C in the flow of O2 after 60 minutes is fit and listed in Figure S13 and Table S4. The fit points to Cu-O distance of ~1.93 Å and Cu-Cu distance of ~ 2.91 Å, average Cu-O and Cu-Cu coordination number of 3.5 ± ± 0.2. These values are very close to the as-synthesized Cu-NU Similar to Cu-NU- 1000, the strong Cu-O multiple scattering feature in the heated sample indicates that Cu species have squareplanar environments. Figure S13. The k 2 -weighted (a) Cu-EXAFS Img[c(R)] and (b) k 2 -χ(k) spectra of Cu-NU-1000 after heated in oxygen at 150 C for 1 h (black) and the obtained fit (magenta) are shown. Table S4. The coordination number, average atom distances, and Debye-Waller factors (DWF) determined for the activated Cu-NU-1000 by fitting the experimental spectrum with a model derived using FEFF9. The fit is obtained using k-weighting of 2. Other parameters: amplitude reduction factor (amp) = 0.83, R-factor = , and E0 = -8.6 Shell a Coordination Number Distance (Å) DWF Cu-O 1 SS 3.5± ± ± Cu-O 2 SS 1 (set) b 2.31± ± Cu-Cu SS 1.3± ± (set) Cu-O 1 MS ± ±0.010 Cu-O 1 MS ± ±0.010 ass = average single scattering; MS = multiple scattering. The fit is obtained using k-weighting of 2. bvalue is set to CN for Cu(OH)2 reference S12

13 The stability of NU-1000 and Cu-NU-1000 The stability of the catalyst was examined to determine appropriate reaction conditions. Figure S14 shows the TG-DSC results obtained for NU-1000 in the flow of synthetic air and N2, respectively. In both cases the weight loss is primarily due to desorption of the physisorbed water from the MOF pores, which is observed already at 50 C and is an endothermic process. Subsequent weight loss is observed at much higher temperatures (~310 C) and is attributed to the removal of H2O-ligands from the nodes of NU Finally, at temperatures above ~350 C we observe further changes: exothermic in synthetic air flow and endothermic in N2 flow. These are due to the deformation of NU-1000, specifically through the oxidation (exothermic) and the pyrolysis (endothermic) of the linkers in the presence and the absence of O2, respectively. We have also tested the stability of Cu-NU-1000 under pure O2. Like in synthetic air, Cu-NU-1000 shows good stability in the presence of O2, the decomposition of the materials is found at temperatures of ~300 ºC (Figure S15). Overall, these TG-DSC measurements show that NU-1000 is stable for the activation of methane at 200 ºC. Figure S14. TG-DSC curves measured for NU-1000 in the flow of synthetic air (left) and in N2 (right) are shown. Figure S15. O2 TG graphs of NU-1000 and Cu-NU The curves were obtained for the samples in oxygen with temperature ramp of 3 K per minute from room temperature to 800 C. S13

14 Figure S16. TG-DSC curves obtained for Cu-NU-1000 in CH4 flow after activation in synthetic air flow (left) and the corresponding MS-signals of the observed TG-DSC test desorption products (right) are shown. Figure S16 shows the TG-DSC curves obtained for Cu-NU-1000 in CH4 flow. In this measurement, a mass spectrometer (MS) was connected to the outlet of TG-DSC analyzer to monitor the formed/desorbed compounds. Cu-NU-1000 was activated at 150 C in the flow of synthetic air for 1 h and then flushed with CH4 prior to starting the temperature ramp in CH4 flow. No changes are detected for temperatures below 150 C. A substantial weight loss is observed at 213 C accompanied by exothermic and endothermic processes at 210 C and 220 C, respectively. Formation of CH3OH and CO2, m/z = 31 and 44, respectively, is observed at 216 C (Figure S16, right). Because under the experiment conditions there is no O2 in the gas phase, the exothermic reaction is attributed to the oxidation of CH4 by the previously O-activated Cu-species deposited in the MOF. We also observe further fragments (m/z = 28, 41, 42, 43. due to CO, CO2 and possibly acetic acid) at 221 C as result of an endothermic process (DSC peak at 220 C). Table S5 shows BET surface area and pore volumes, Figure S17 lists the N2 adsorption-desorption isotherms for Cu-NU-1000 before and after catalysis. The decrease in the BET surface area and pore volume for Cu-NU-1000 compared to NU-1000 is probably due to the sitting of Cu in the pores. The BET surface area and pore volume of Cu-NU-1000 remain almost unchanged after 3 reaction cycles. However, when 50/50 water vapor and He were used to desorb the products, we observed a notable decrease in BET surface area and pore volume even after the first catalytic cycle. It suggests that the structural degradation of the MOF lattice is likely due to the large amount of water vapor in the gas phase during the last steam-assisted products desorption. Table S5. N2 adsorption properties of Cu-NU-1000 before and after reactions. Sample BET surface area (m 2 g -1 ) Pore volume (cm 3 g -1 ) NU Cu-NU Cu-NU-1000 after 1 cycle a Cu-NU-1000 after 3 cycle a Cu-NU-1000 after 1 cycle b S14

15 a H2O:He = 1:9 in the third step; b H2O:He = 1:1 in the third step. Figure S17. N2 adsorption and desorption isotherms measured at 77 K of parent NU1000, and Cu-NU1000 before and after reaction. The stability of Cu-NU-1000 was analyzed during the activation step in O2. Figure S18 shows TG curve as well as MS signals at 200 C. A weight loss of ca. 4% was observed during heat up, which can also be seen in Figure S15. When the temperature was held at 200 C for 3 hours, an additional weight loss of ca. 4% was observed. Analysis of the gas products during the activation treatment in the thermobalance showed that the overall weight loss is due not only to dehydration but also to the decomposition of remnants from the Cu complex used for the synthesis of Cu-NU Besides dehydration of the catalyst (m/z = 18), the fragments m/z = 28, 30, 44, 45 were observed (Figure S18), which correspond to fragment ions from the dmap ligand (see Figures S1 and S21) and/or its partial oxidation products. These m/z were only detected for fresh samples under oxidative activation and were not detected during methane activation or steam treatment. Figure S18. TG curve and MS signals during activation of Cu-NU-1000 in the presence of O2. The TG curve was obtained in the flow of synthetic air (16 ml/min) and MS signals were recorded during activation in pure O2 (16 ml/min). The stability of Cu-NU-1000 was further tested by TG analysis of fresh and used Cu-NU-1000 in N 2 flow. The TG curve of the material after one catalytic cycle is unchanged from the fresh material (Figure S19). The XRD patterns of the Cu-NU before and after reaction were also compared (Figure S20). The crystallinity of Cu-NU-1000 is not decreased after one reaction cycle, in good agreement with the results from N 2 adsorption and TGA. All these results show that the Cu-NU-1000 material is stable under the conditions applied for methane oxidation to methanol. S15

16 Figure S19. N2 TG curves of Cu-NU-1000 before and after a reaction cycle. The measurements were carried out during ramping at 3 K/min from room temperature to 400 C in N2 flow. Figure S20. Powder XRD patterns of Cu-NU-1000 before reaction, after reaction with CH4 and after desorption of the products by steam treatment in 10% H2O and 90% He. S16

17 Analysis for remnants of the dmap ligand in Cu-NU-1000 Figure S21 shows an 1 H-NMR spectrum of a digested sample of the as-synthesized Cu-NU The peaks marked with the peaks marked with an symbol are from the dmap ligand. In addition, Additional unmarked peaks are seen which may be remants of the decomposed dmap ligand and/or solvent from the synthesis of NU Using the pyrene ligand ( ) as internal standard, the amount of the decomposed ligand is roughly estimated to be ~1.5 molecules per node. Analysis Cu- NU-1000 after activating in O 2 at 200 C for 1 hour showed the amount of dmap contaminant had decreased to ~0.5 molecules per node. Figure S21. 1 H-NMR spectrum of an acid-digested Cu-NU-1000 sample in D2SO4/DMSO. Peaks marked with symbols are from the NU-1000 linker and peaks marked with symbols are from the dmap ligand. S17

18 Additional EXAFS data for A and A-2node Figure S22. The k 2 -weighted Cu-EXAFS Img[χ(R)] spectra of Cu-NU-1000 (black) and A (simulated, red) are shown. Figure S23. The k 2 -χ(k) Cu-EXAFS spectra of Cu-NU-1000 (black) and A-2node (simulated, red) are shown. S18

19 Alternative structures for Cu n -NU-1000 (n = 1 4) In order to account for the disorder experimentally observed, we have computed different cluster models for Cun-NU-1000 (n = 1 4). For n = 1 2, one Zr6-node model with eight linkers truncated as benzoate groups was employed. The most relevant structures are shown in Figure S24. Poor agreement with EXAFS spectra was found due to the low nuclearity of the clusters. For n = 3 4, one Zr6-node model with eight linkers truncated as formate groups was used. Despite the inclusion of additional explicit water molecules, no six-coordinate Cu centers could be found. Instead, during optimization some water molecules were expelled from the first coordination sphere of the metals. The most relevant structures and energies are shown in Figure S25. Species 4Cu-b was designed to mimic cubane-like structures as reported in literature. 6 cis trans cis-1cu trans-1cu Å Zr Cu O C H 2Cu Figure S24. DFT-optimized structures of Cu1- and Cu2-NU Zr Cu O C H av. Cu Cu = Å 3Cu-a ΔE [ΔG] 0.0 [0.0] av. Cu Cu = Å 3Cu-b ΔE [ΔG] 10.6 [ 9.7] 4Cu-a ΔE [ΔG] 0.0 [0.0] 4Cu-b ΔE [ΔG] 16.8 [16.0] av. Cu Cu = Å av. Cu Cu = Å Figure S25. DFT-optimized structures of Cu3- and Cu4-NU Relative energies in kcal mol 1. S19

20 Of the structures shown in Figures S24 and S25, 3Cu-b came closest to fitting the experimental EXAFS data (see Figure S26), although the fit was not nearly as good as for the A-2node (Figure 8 in the main text). Figure S26. The k 2 -weighted Cu-EXAFS Img[χ(R)] spectra of Cu-NU-1000 (black) and 3Cu-b (simulated, red) are shown. Periodic vs cluster calculations Average bond distances are collected in Table S5 for A-2node using the two-node cluster (M06-L) and the periodic structure of NU-1000 (PBE-D3). Table S6. Average distances in Å between Cu atoms and their nearest neighbor atoms for A-2node. Methodology Cu Cu / Å Cu O / Å Cu Zr / Å Cluster M06-L 2.979± ± ±0.045 Periodic PBE-D ± ± ±0.030 S20

21 Cartesian coordinates XYZ and CIF coordinates for all DFT-optimized structures. Energies and Gibbs energies in Hartrees. Frequencies below 50 cm 1 were replaced by 50 cm 1 when computing vibrational partition functions. 21 A E= Cu Cu O H O H O H O O H O H Cu O O H H H H H A-2node E= C C C C H H H H H H H H O O O O O O O O O O O O O O O O Zr Zr C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C S21

22 C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O S22

23 O O Zr Zr Zr Zr Zr Zr Zr Zr Zr Zr H H H H H H H H Cu O H O H O H O H Cu Cu H H H H H H H H cis-1cu E= C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H O O O O O O O O S23

24 O O O O O O O O O O O O O O O O O O O O O O O O Zr Zr Zr Zr Zr Zr Cu H O H O H H O H H trans-1cu E= C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H O O O O O O O S24

25 O O O O O O O O O O O O O O O O O O O O O O O O O Zr Zr Zr Zr Zr Zr Cu O H H O H H O H H Cu E= C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H O O O O O O O O S25

26 O O O O O O O O O O O O O O O O O O O O O O O O Zr Zr Zr Zr Zr Zr Cu Cu H H O H O H O H O H H H Cu-a E= G= C C C C C C C C H H H H H H H H H H H H H H O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O Zr Zr Zr Zr Zr Zr Cu O H H O H Cu O H O H O H H O H O H H Cu O H O H H O H H O H H H H H H H H H H H Cu-b E= G= C C C C C C C C H H S26