www.sciencemag.org/content/344/6184/616/suppl/DC1

Supplementary Materials for

Direct, Nonoxidative Conversion of Methane to Ethylene, Aromatics,

and Hydrogen

Xiaoguang Guo, Guangzong Fang, Gang Li, Hao Ma, Hongjun Fan, Liang Yu, Chao Ma,

Xing Wu, Dehui Deng, Mingming Wei, Dali Tan, Rui Si, Shuo Zhang, Jianqi Li, Litao

Sun, Zichao Tang, Xiulian Pan, Xinhe Bao*

*Corresponding author. E-mail: xhbao@dicp.ac.cn

Published 9 May 2014, Science 344, 616 (2014)

DOI: 10.1126/science.1253150

This PDF file includes:

Materials and Methods

Figs. S1 to S7

Tables S1 to S3

Full Reference List

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Materials and Methods

Experimental details and Characterization

Catalyst preparation

0.5% Fe©SiO2 catalyst: 6 g commercial SiO2 with a BET surface area< 1 m2/g and 112 mg Fe2SiO4 were mixed and subjected to ball milling under high purity argon (99.999%) at 450 rev. /min for 15 h. Next, the mixture was fused at 1973 K for 6 h in air. Commercial quartz was obtained from Hubei Jinxin quartz Ltd. The obtainedcatalysts were subjected to leaching using aqueous HNO3 (0.5 mol/L), and then dried at 353 K for 12 h. The Fe loading was 0.5 wt. %.

0.5% Fe/HZSM-5 catalyst: This catalyst was prepared by an impregnation method. Briefly, 6 g commercial HZSM-5 (Zeolyst, 3024E, Si/Al=15, BET surface area 405 m2/g) was added to 5.2 mL aqueous Fe(NO3)3 (0.11 mol/L). Water was evaporated by stirring for 12 h at ambient conditions and further at 333 K for 24 h. Finally, the solid was calcined at 823 K for 6 h. The Fe loading was 0.5 wt. %.

0.5% Fe/SiO2 catalyst: This catalyst was also prepared by an impregnation method. 6 g commercial silica (Qingdao Ocean Chemical Company, BET surface area 348 m2/g) was functionalized with H2N-(CH2)3Si(OEt)3 (36), followed by addition of 5.2 mL aqueous Fe(NO3)3 (0.11 mol/L). The mixture was dried under stirring for 12 h and further at 333 K for 24 h. Finally, the solid was calcined at 823 K for 5 h. The Fe loading was 0.5 wt. %.

0.8% Fe/SiO2 catalyst: This catalyst was prepared using a sol-gel method. 20.8 g tetraethoxysilane (TEOS) was mixed with 331 mg Fe(NO3)3·9H2O and 4 mL ethanol in 24 g aqueous nitric acid (15wt.%), then stirred at 333 K for 24 h, followed by aging for 24 h. The resulting gel was dried in a rotary evaporator at 353 K for 2 h and further treated at 1973 K in flowing He for 6 h. The loading of Fe was 0.8 wt. %.

0.2% Fe/SiC catalyst: Firstly, 6 g commercial α-SiC (Alfa Aesar, BET surface area 11.1 m2/g) and 112 mg Fe2SiO4 were mixed and subjected to ball milling under high purity argon (99.999%) at 450 rev. /min for 10 h. The milled mixture was heated at 1973 K for 6 h in flowing Ar. The initial loading of Fe was 0.5 wt. %. The resulting sample was subjected to leaching using aqueous HNO3 (0.5 mol/L), and then dried at 353 K at 12 h. The final loading of Fe was 0.2 wt. %.

Catalytic reactions

Reactions were carried out in a continuous flow, fixed-bed reactor. In all reaction tests, 0.75 g catalyst was packed in the reactor, unless otherwise stated. For the reaction at 1363 K, 0.375 g catalyst was used.The feed gas composed of 10 vol. % N2 and 90 vol. % CH4, with N2 as an internal standard,was passed through deoxygen and dehydration immediately prior to use. The effluent composition was monitored by an online Gas chromatography (GC) (Agilent 7890A), which is equipped with an FID detector with HP-1 capillary column; a TCD detector with Hayesep D packed column. Methane conversion,

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hydrocarbon product selectivity and coke deposition selectivity were calculated according to the carbon balance, following a previously reported method (20, 37).

H2 analysis

10 vol. % N2was used as the internal standard for product analysis by GC. The amount of H2 produced in a particular experiment was calculated from the corresponding peak area, using the appropriate sensitivity factor. Fig. 1D shows the H2 peaks recorded by GC, normalized using the N2 peak, at different reaction temperatures (the lower panel). For example, at 1223 K with a space-velocity of 4.84 L·gcat

-1·h-1, the H2 content is 10.9%. The amount of H2 produced can also becalculated from the mass balance, i.e., methane

conversion and the selectivities towards ethylene, benzene and naphthalene, since no other products were detected. Also taking the reaction at 1223 K as an example, the reaction stoichiometry can be described as:

CH4 = 3/52 C6H6 + 5/104 C10H8 + 9/104 C2H4 + 19/13 H2 Under these conditions, methane conversion is 8.1%, ethylene selectivity 47.6%,

benzene selectivity 26.2%, and naphthalene selectivity 26.1%. Thus, the calculated H2 concentration in the effluent is 11.0%, which is practically the

same as that measured directly from GC analysis. Fig. 1D compares the H2 content at different reaction temperatures. It demonstrates that both methods for H2 analysis give consistent results.

Catalyst characterization

Scanning transmission electron microscopy (STEM) was performed on a JEOL ARM200F equipped with double aberration correctors and a cold field emission gun operated at 200 kV. STEM images were recorded using a high-angle annular dark-field (HAADF) detector with convergence angle of 30 mrad and collection angle between 90 and 370 mrad. Under these conditions, the spatial resolution is ca. 0.08 nm. Since the brightness in the Z-contrast STEM images is proportional to Zn (1 < n < 2, where Z is the atomic number), iron clusters and even single iron atoms embedded in amorphous SiO2 can be clearly distinguished. High-resolution TEM (HRTEM) was performed with a FEI Tecnai G2 Spirit transmission electron microscope operating at 120 kV.

X-ray absorption spectra (XANES and EXAFS) were measured at the BL14W1 beamline of Shanghai Synchrotron Radiation Facility (SSRF), which operates at 3.5 GeV in “top-up” mode with injection current of 220 mA. The Fe K-edge XANES data were recorded in a fluorescence mode. Fe foil (99.99%), FeSi2 (99.5%, Alfa Aesar) and Fe2O3 (99.5%, Alfa Aesar) were used as references. For XANES and EXAFS analysis, the data was extracted using the Athena software.

Density functional theory (DFT) calculations on CH4 activation

DFT calculations on the surface reaction thermodynamics and kinetics were performed using the Vienna Ab-initio Simulation Package (VASP) (38-40). The projector

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augmented-wave pseudopotentials and a cutoff energy of 400 eV for the plane-wave basis set were adopted (41, 42). The Generalized Gradient Approximation (GGA) method with Perdew-Burke-Ernzerhof (PBE) functionals for the exchange-correlation term was used (43, 44). The Monkhorst-Pack scheme was used for sampling the Brillouin zone (45). The stable crystal phase of silicon dioxide at the reaction temperature (1173~1350K), i.e., beta-tridymite, was adopted as the matrix of the catalyst. The isolated iron site was simulated on the (001) surface of beta-tridymite with SiO3 substituted by one Fe atom (structure (i) in Fig. S5) in a 2×2 supercell. The dangling bonds at the surface Si sites were saturated by OH groups. Spin polarization was considered throughout the calculations. The transition states were searched using the constrained minimization approach (46-48). The free energies of the reactants, surface intermediates, and products were obtained as G = Etotal + ZPE – TS, where Etotal is the total energy of the species, ZPE is the zero-point energy and S is the entropy. The entropies of gas-phase species were obtained from the literature (49).

In situ ultraviolet soft photoionization molecular-beam mass spectrometry (VUV-SPI-MBMS)

Considering that radicals have very short mean-free paths, we designed a home-made setup using vacuum ultraviolet soft photoionization molecular-beam mass spectrometry to monitor the reactor effluents (Figure 3a and 3b). MBMS coupled with threshold ionization has been recently employed in studies of heterogeneous catalysis (35, 50-53).

In this work, a quartz U-tube with an outer diameter of 6 mm and an inner diameter of 4 mm was used as the reaction chamber. It was heated electronically using a tungsten heater. A mixture of 90 vol. % CH4 and 10 vol. % N2 was used as the feed gas. The flow rate and reaction temperature were varied from10 – 30 mL/min and 1173 – 1253 K, respectively. The effluent from the nozzle depicted in Fig. S6b was collected into the skimmer using a cone-like orific (ID = 0.5mm). Supersonic expansion effect of the molecular beam can prevents the collision of stable and unstable species, allowing detection of radicals, intermediates and products. Then, the molecular beams were subjected to single-photon ionization by a commercial VUV Lamp (10.6 eV) in the photoionization chamber, which was coupled to a homemade reflection time-of-flight mass spectrometer (RTOF-MS) (54). The working pressures of the catalysis chamber and the photoionization chamber were 5×10-4 and 3×10-5 Pa, respectively. The ions were drawn out of the photoionization region by a pulse extraction field triggered, and detected by a microchannel plate (MCP) detector. The ion signal was recorded by a multiscaler after amplification.

Reaction profiles for methyl radicals in the gas phase at 1225 K simulated by DFT

DFT calculations were carried out using the Jaguar 7.8 (55) suite of ab initio quantum chemistry programs. Geometry optimizations were performed with the M06-

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2x(56)functional and the Dunning’s correlation-consistent triple-basis set (57) cc-pVTZ(-f) that includes a double set of polarization functions. Vibrational frequency calculations based on analytical second derivatives at the same level of theory were carried out to derive the Zero-Point-Energy (ZPE) and entropy corrections at 1225 K using unscaled frequencies.

The mechanisms discussed here are comprised of several homolytical bond dissociation processes. According to an earlier study (58), DFT is quite good at calculating bond dissociation energies, while MP2, on the other hand, gives much larger errors. Therefore we chose DFT as the major method for this work.

The energy components were computed following the protocol of our previous work. Free energies in the solution phase, G(sol), were calculated as follows (59):

G(gas) = H(gas) - TS(gas) (1)

H(gas) = H(SCF) + ZPE (2)

where G(gas) = free energy in gas phase; H(gas) = enthalpy in gas phase; T =

temperature (1225K); S(gas) = entropy in gas phase; H(SCF) = self-consistent field energy, i.e., “raw” electronic energy as computed by the SCF procedure; ZPE = zero point energy.

Reaction profiles for 2CH3 C2H4+ H2.

C2H6 is readily formed by the combination of two ·CH3 radicals: 2CH3 C2H6, The

barrier is estimated by assuming that the barrier for AB A· + B· is equal to H for the

reaction. For C2H6 C2H4+ H2, we have considered three different pathways: Path A (Fig. S7a in black), C2H4 is formed by two, sequential bond dissociation

processes.

C2H6 C2H5+ 1/2 H2

C2H5 C2H4+ 1/2 H2

Path B (Fig. S7a in green),C2H6 is transformed to C2H5 with the help of a ·CH3

radical:

C2H6 + CH3 C2H5+ CH4

C2H5 C2H4+ 1/2 H2

Path C (Fig. S7a in red), Dehydrogenation of C2H6 is catalyzed by the ·H radical.

C2H6 + H C2H5+ H2

C2H5 C2H4+ H For path A, the first dissociation is rather difficult, and the overall barrier is 4.28 eV. In

comparison, the barriers for path B and C are significantly lower, 2.42 eV and 1.58 eV,

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respectively. The ·H radical required for path C can be generated in path B. In the presence of ·H radicals, path C is preferred, and the reaction is expected to be very fast at 1225 K. This explains why C2H6 is not observed in our experiment.

Reaction profiles for 3C2H4 C6H6+ 3H2

Fig. S7b shows the reaction pathway we propose for 3C2H4 C6H6+ 3H2. As in a typical radical reaction, the steps are radical generation, radical transformation and radical termination.

a) Radical generation. There are two ways to generate the active radical ·C2H3:

C2H4 + ·CH3 ·C2H3 + CH4 G(1225 K) = -0.29 eV, G(1225 K) = 2.15 eV.

C2H4 + ·H ·C2H3 + H2 G(1225 K) = -0.99 eV, G(1225 K) = 1.61 eV. b) Radical transformation. C2H3 reacts with two C2H4 molecules to give C6H7, after

dehydrogenations and cyclization.

c) Radical termination. The radical reaction is terminated by C-H bond dissociation of

C6H7 resulting in formation of benzene.

The reaction has a high overall barrier (2.85 eV). The C2H4 transformation is much

more difficult than its formation, thus C2H4 can accumulate under reaction condition. A large barrier also implies that the reaction requires high temperature to proceed. The ·H radical used to generate the ·C2H3 active species is regenerated at the last step. Thus ·H radical acts as a catalyst for the reaction.

We have also evaluated an alternative pathway where C4H7 reacts with C2H4 leading to C6H11, followed by cyclization and dehydrogenation. This pathway needs to overcome a barrier that is 0.32 eV higher than that in Fig. S7b.

Dehydrogenation reactions of radicals are composed of two elementary steps, for example, as shown below for C4H7:

C4H7 C4H6 + H

C4H6 + H C4H5 + H2 The C-H bond dissociation in such a radical occurs much more readily than H

abstraction reaction. In contrast, the C-H bond dissociation in non-radical species such as

+

+ H2

+

+ H2

+ H

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C4H6 is more difficult than the corresponding H atom abstraction reaction. H atom abstraction from radical species is also easy, although in that case, the dehydrogenation reaction consumes ·H radicals.

Reaction profiles for C6H6 + 2C2H4 C10H8+ 3H2.

The reaction pathway for C6H6 C10H8 (Fig. S7c) also involves radical generation, radical transformation and radical termination. a) Radical generation. There are two ways to general the active radical C6H5.

C6H6 + CH3 C6H5 + CH4 G(1225 K) = +0.44 eV.

C6H6 + H C6H5 + H2 G(1225 K) = -0.26 eV. b) Radical transformation. C6H5 reacts with two C2H4 molecules to give C10H8, after

dehydrogenations and cyclization.

c) Radical termination. The radical reaction is terminated by C-H bond dissociation in

C10H9, leading to the formation of C10H8.

The calculated barrier for C6H5 + 2C2H4 C10H8+ 2H2 + H is 2.52 eV at 1225 K.

However, there is a faster reaction channel for C6H5 and C2H4 which is to form C6H6

and ·C2H3 (G = -0.73 eV, barrier: 2.26 eV). Therefore the overall barrier for formation of C10H8 from C6H6 is 3.25 eV. This barrier is higher than that from C2H4 to C6H6. Therefore, the formation of C6H6 is faster than its consumption, and C6H6 can accumulate during the reaction. A high barrier also means that the reaction requires a high temperature. Consequently the formation of C10H8 is slow. The dehydrogenation of radicals is again comprised of two steps, as discussed above. The ·H radicals used to generate the C6H5 active species are regenerated in the last step. Therefore, ·H radical acts as a catalyst for this reaction.

We have also evaluated an alternative pathway where C6H5C2H4 reacts with C2H4 to give C6H5C4H7, followed by cyclization and dehydrogenation. This pathway needs to overcome a barrier 0.10 eV higher than that in Fig. S7b.

+

+ H2

+

+ H2

+ H

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Further description

1) ·H radical catalysis or ·CH3 radical abstraction? As discussed above, the dehydrogenation of non-radical species is difficult, but can be

accelerated by a) ·CH3 radicals abstraction, for example in Fig. S7a, C2H6 + ·CH3

C2H5 + CH4, or b) H atom catalysis: C2H6 + H C2H5 + H2. H is regenerated by C2H5

C2H4 + H, which is facile under the reaction conditions. If this dehydrogenation undergoes ·CH3 abstraction, then forming one C10H8 molecule will consume 11 ·CH3 radicals, and the total conversion will be very low (which is not consistent with our experimental results). Fig. S7a clearly indicates that the ·H radical catalyzed mechanism has a lower barrier than ·CH3 radical abstraction pathway. Therefore, we propose the reaction most likely proceeds via an ·H radical catalyzed mechanism. The catalyst ·H radical can be easily generated in the gas phase by ·CH3 radical and C2H5 according to

the processes: C2H6 + ·CH3 ·C2H5 + CH4 and ·C2H5 C2H4 + ·H. Therefore, ·CH3 plays an essential role since it generates the active catalyst H, which has initiated the whole reaction and further compensated the consumed catalyst by side reactions such as

H + H H2. The presence of ·CH3 is crucial for the formation of C2H4, C6H6 and C10H8. Otherwise the catalyst H can only be generated by breaking the C-H bond of C2H6, which needs to overcome a barrier of 4.28 eV. This is much higher than the barriers for the rate-determining steps (formation of C6H6, 2.85 eV, and C10H8, 3.25 eV). In other words, breaking the C-H bond of C2H6 is facile, all other reactions would be extremely fast and the reaction would not stop at the products C2H4, C6H6, or even C10H8.

2) What about C3 species? Transformation of C2H4 and H2 to C3 species is thermodynamically unfavorable, and

the reverse reaction will happen if it is not too slow.

C2H4 + 2/3 H2 2/3 C3H8 G = +0.46 eV

C2H4 2/3 C3H6 G = +0.12 eV However, C3 species could be fromed from C2 species via the following reactions:

C2H5 + CH3 C3H8 G = -1.44 eV

C2H4 + CH3 C3H6 + 1/2 H2 G = -0.83 eV Both reactions consume ·CH3 radicals, and thus can only be favorable at the beginning

of the reaction when the concentration of ·CH3 is not too low. 3) Relative concentrations of C2H4, C6H6 and C10H8 products. C2H4 forms readily in the presence of ·CH3 radicals. C4H6 and C10H8 are

thermodynamically more stable than C2H4, but the transformation from C2H4 to C6H6 is slow (barrier 2.85 eV). The transformation from C6H6 to C10H8 is even more difficult (barrier 3.25 eV). The reaction profiles predict that at the beginning of reaction C2H4 will be the dominant product. Subsequently, the concentration of C2H4 will decrease as the concentration of C6H6 increases. C6H6 is then transformed slowly to C10H8. The rate of C6H6 formation also decreases dramatically with the reaction time because the

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C2H4concentration decreases. The concentration of C6H6 reaches a maximum at a certain time when the rates of formation and consumption are equal. After that time, the concentration of C6H6 decreases.

4) Why only C2H4, C6H6 and C10H8? Although there are many intermediates in our reaction pathway, only C2H4, C6H6 and

C10H8 were detected in our experiments as the final products. This is because other possible intermediates, such as C4H6 (obtained by C-H bond dissociation of the intermediate C4H7), are either higher in energy than the observed species, or are transformed in kinetically facile reactions to one of these observed species.

5) According to calculated reaction energies at 1225 K:

3C2H4 C6H6 + 3 H2 G = -2.01 eV

5C2H4 C10H8 + 6 H2 G = -3.42 eV When the equilibrium is reached, almost all C2H4 is converted to C10H8. Thus we do

not achieve the equilibrium in our experiments, and a longer reaction time (or lower space velocity) yields more C6H6/C10H8.

6) Temperature dependence.

At 1325 K, the reaction barrier for C2H4 C6H6 is 2.99 eV. According to Arrhenius equation, k = Aexp(-Ea/RT), the rate at 1325 K is estimated to be about twice as that at 1225 K. Therefore the reaction profile predicts that the reaction rates increase with the

temperature. For C6H6 C10H8, the barrier is 3.43 eV at 1325 K, and the reaction is also estimated to be about twice as fast as it is at 1225 K.

Optimized geometries (in Å) and computed energies (electronic energy, eV)

=============================== CH3 E=-1083.664

=============================== C -0.223363031 0.406161833 0.016199829 H -0.262854760 1.481853498 0.016205788 H -0.262605166 -0.131395105 0.947835019 H -0.262605317 -0.131403946 -0.915438766

=============================== C2H6 E=-2171.591

=============================== C -0.166630564 0.407720625 0.016252812 C 1.146213564 -0.369101165 -0.017992548 H -1.021315686 -0.265701636 0.058152398 H -0.278472380 1.030299549 -0.870017600 H 1.195599271 -1.020084607 -0.889496964 H 2.000801416 0.304396627 -0.058550486 H -0.215165493 1.059178380 0.887368651 H 1.257555289 -0.992520019 0.867917127

=============================== C2H5 E=-2153.345

=============================== C 0.692142948 -0.000000605 0.000238139

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H 1.099257667 -0.883307060 -0.490475491 C -0.791278725 0.000000506 -0.029901766 H 1.099261079 0.883250678 -0.490573565 H 1.075693640 0.000055769 1.027198758 H -1.340901312 0.922572385 0.064913808 H -1.340902711 -0.922577493 0.064844759

=============================== CH4 E=-1102.083

=============================== C -0.164166946 0.406191371 0.016200024 H 0.921204727 0.406272530 0.016165611 H -0.526023829 1.429536834 0.016238143 H -0.526120198 -0.105430239 0.902331561 H -0.526063583 -0.105476382 -0.869935600

=============================== C2H3 E=-2119.887

=============================== C -0.147103611 0.432382508 0.015165159 C 0.937213698 -0.303222248 -0.011586285 H -1.147194352 -0.012716639 0.057959724 H -0.113195447 1.521163703 -0.003603063 H 1.192778323 -1.354959012 -0.003721270

=============================== TS C2H4+H->C2H3+H2 E=-2150.801

=============================== C -0.196426162 0.421510775 0.014156471 C 0.908517682 -0.282144289 -0.010080404 H -1.395672964 -0.336171272 0.062825113 H -0.356338477 1.490395610 0.004815353 H 0.888661092 -1.365750150 0.004636002 H 1.885018142 0.191470761 -0.046147876 H -2.091867083 -0.864015736 0.096714824

=============================== H2 E=-32.07

=============================== H -0.207047263 0.527499458 0.016200000 H -0.454952737 1.227500542 0.016200000

=============================== TS C2H4+CH3->C2H3+CH4 E=-3220.906

=============================== C -0.270341548 0.455197940 0.014227008 C 0.782090464 -0.330814082 -0.003074150 H -1.490241178 -0.158631130 0.055576811 H -0.291823561 1.537480571 -0.000863918 H 0.681018963 -1.410341732 0.015217857 H 1.793564233 0.062843406 -0.036488169 C -2.613917172 -0.834201156 0.095357044 H -2.313434688 -1.875293651 0.148147056 H -3.131585204 -0.582160648 -0.823705660 H -3.123671666 -0.488128693 0.987926073

=============================== TS C2H4+C2H3->C4H7 E=-4257.287

=============================== C -1.413013908 -0.486518001 -0.181651965 C -0.834846565 0.665955383 0.013857012 H -2.483654877 -0.570344681 -0.345218489

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H -0.835661439 -1.404888318 -0.187536177 H -1.199842334 1.680979532 0.060674847 C 1.450275197 0.619033280 0.354012295 C 1.844555192 -0.662433578 0.274359376 H 1.270567097 1.084498066 1.313214692 H 1.547425289 1.281994737 -0.494542712 H 2.129993403 -1.105586193 -0.669207041 H 1.852040639 -1.303815287 1.144292462

=============================== C4H7 E=-4259.015

=============================== C -0.104335730 0.263445353 -0.223353003 C 1.008225552 -0.211787381 0.315713173 H -1.050953062 -0.246775596 -0.111629581 H -0.101564628 1.182409190 -0.797174527 H 0.973844933 -1.137679292 0.881464344 C 2.358458955 0.432250397 0.191581812 C 3.349667147 -0.453803690 -0.482921219 H 2.729276041 0.698494232 1.186090311 H 2.250314648 1.379635444 -0.353047639 H 4.408834841 -0.292490545 -0.355050397 H 3.022401722 -1.162979463 -1.227497365

=============================== TS C4H7+C2H4->C6H11(chain) E=-6396.784 ===============================

C -0.004765264 0.270092675 -0.323061190 C 1.047708507 -0.138148523 0.368820287 H -0.977492934 -0.182708881 -0.192697343 H 0.073964643 1.076367619 -1.041903268 H 0.936200390 -0.951272931 1.078611393 C 2.438414356 0.420756822 0.224173541 C 3.382818699 -0.628192033 -0.287310706 H 2.783516595 0.785697573 1.195404110 H 2.410381133 1.274749463 -0.455097111 C 5.364373788 0.429223518 -0.392603048 H 3.271982117 -0.926454604 -1.320816766 H 3.649156623 -1.430427597 0.387728609 H 4.914827929 1.145632751 -1.067095470 C 6.329199025 -0.408605159 -0.830498362 H 6.534101637 -0.529171745 -1.884373896 H 6.886526443 -1.031253873 -0.145623819 H 5.266769143 0.646712269 0.662736060

=============================== C6H11(chain) E=-6398.206

=============================== C -0.100819909 0.217796550 -0.316401632 C 0.973005243 -0.158626520 0.359475550 H -1.049567702 -0.286519680 -0.200509016 H -0.063569420 1.049515374 -1.009198409 H 0.897348177 -0.998187560 1.044326338 C 2.326275283 0.472050623 0.241673380 C 3.380298660 -0.512387422 -0.263218169 H 2.640336548 0.847893858 1.220179232 H 2.272282996 1.332374077 -0.428652977 C 4.771614206 0.109004297 -0.344239995 H 3.087419861 -0.879541106 -1.249041951

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H 3.413598492 -1.381926369 0.398017094 H 4.734892451 0.993930179 -0.992648948 C 5.808829928 -0.836103697 -0.832410920 H 6.836414016 -0.526596307 -0.938700304 H 5.552947005 -1.852029468 -1.090994974 H 5.051932720 0.497605259 0.643357232

=============================== TS C6H11(chain)->C6H11(ring) E=-6397.769 ===============================

C 0.514745029 0.668855995 -0.785730495 C 1.940920065 0.426070456 -0.393485184 C 1.924941781 -1.846403688 -0.390650770 C 0.874537515 -2.024595072 0.438465940 C -0.481657877 -1.536300358 0.040892090 C -0.515255033 0.001940722 0.133089083 H 0.317726317 1.748066645 -0.798724861 H 0.350926502 0.327228219 -1.812463767 H 2.712031996 0.649611235 -1.119829599 H 2.212528976 0.621587689 0.635859398 H 1.764770250 -1.748483370 -1.457741973 H 2.932796095 -2.085936722 -0.081447484 H 1.046954910 -2.261912282 1.481000454 H -0.697784891 -1.822977691 -0.991611681 H -1.263497720 -1.960788687 0.670110571 H -1.514189770 0.355433875 -0.126570508 H -0.327021583 0.305878186 1.165883402

=============================== C6H11(ring) E=-6399.271

=============================== C 0.584381877 1.120871832 -0.844131230 C 1.950338715 0.590276921 -0.416900513 C 1.948672610 -0.943466080 -0.392692594 C 0.805253302 -1.465659036 0.409453433 C -0.547534469 -0.894792532 0.153446753 C -0.504877092 0.637565576 0.109470828 H 0.595153936 2.210225180 -0.885715887 H 0.361871167 0.765778157 -1.855003842 H 2.731198954 0.955346012 -1.084375548 H 2.179574171 0.962145330 0.584529465 H 1.861856154 -1.295862135 -1.431459567 H 2.895114575 -1.327804216 -0.013576139 H 0.898110505 -2.412598811 0.920942737 H -0.920929909 -1.250069212 -0.818794259 H -1.261129017 -1.238589138 0.901981398 H -1.477749564 1.030386083 -0.186890193 H -0.294004456 1.017775494 1.111795358

=============================== C6H10(ring) E=-6384.025

=============================== C 0.586195660 1.106989524 -0.867872151 C 1.934949536 0.589249763 -0.378041259 C 1.958120866 -0.937600039 -0.405695385 C 0.702694900 -1.521511751 0.182784355 C -0.395362877 -0.813410690 0.412949724 C -0.529917088 0.644800674 0.066567504 H 0.591030692 2.194310475 -0.943189085

13

H 0.399494753 0.715850908 -1.871246231 H 2.748523631 0.991486881 -0.981578004 H 2.094923984 0.932332049 0.647337003 H 2.076165739 -1.290349903 -1.435103416 H 2.824032269 -1.314923326 0.141031987 H 0.714403212 -2.574925269 0.433122056 H -1.248423432 -1.294439842 0.874779758 H -1.505085859 0.819720676 -0.391322973 H -0.518438031 1.238637373 0.985809410

=============================== TS C6H10(ring)+H->C6H9(ring)+H2 E=-6397.192

=============================== C 0.577254738 1.119496250 -0.845306099 C 1.942600523 0.577933089 -0.419727257 C 1.927040205 -0.938139378 -0.431600647 C 0.696250492 -1.537463096 0.126015862 C -0.382375703 -0.817616716 0.426590656 C -0.498735310 0.652963102 0.133208364 H 0.596298106 2.207863829 -0.900461876 H 0.341085951 0.747230837 -1.844641991 H 2.735880061 0.959647947 -1.060686439 H 2.153971058 0.924553323 0.595722277 H 2.244497286 -1.387684724 -1.372149464 H 2.863982039 -1.304279612 0.320231496 H 0.699052688 -2.604255787 0.314124415 H -1.237157779 -1.306697789 0.877464449 H -1.492622880 0.862873085 -0.265486073 H -0.422902645 1.219014415 1.067038483 H 3.637158617 -1.544930134 0.940816837

=============================== C6H9(ring) E=-6366.503

=============================== C 0.580607574 1.173548596 -0.781730317 C 1.892806411 0.474386787 -0.604422619 C 1.944148633 -0.815960587 -0.110429490 C 0.803406949 -1.523365483 0.217336549 C -0.551949563 -0.899995330 0.087292045 C -0.466402478 0.622904982 0.186839319 H 0.701455526 2.248375371 -0.642121410 H 0.227055490 1.038018099 -1.811185742 H 2.803293108 0.979774044 -0.892354855 H 2.907978060 -1.294006890 0.008114431 H 0.883013898 -2.543872153 0.563262264 H -0.994298533 -1.175955231 -0.877534033 H -1.223584087 -1.295110844 0.850657055 H -1.439590277 1.073403999 -0.006732176 H -0.177579846 0.892201853 1.204548397

=============================== C6H8(ring) E=-6350.687

=============================== C 0.668906448 1.170810960 -0.639463917 C 1.800756472 0.474668593 -0.741882952 C 1.921252240 -0.844014745 -0.110428483 C 0.832574689 -1.501855740 0.286021247 C -0.533182563 -0.905371214 0.067872031 C -0.488131433 0.619781437 0.152240866

14

H 0.587630605 2.157916107 -1.073182796 H 2.647663785 0.874904567 -1.281041689 H 2.902052835 -1.286635413 -0.003323941 H 0.911341786 -2.494003959 0.710213644 H -0.885709963 -1.206131906 -0.926052992 H -1.249569967 -1.302650128 0.785763370 H -1.430075278 1.045110365 -0.191510251 H -0.369583555 0.923539498 1.199142151

=============================== TS C6H8+H->C6H7+H2 -6363.975

=============================== C 0.670319559 1.173266233 -0.639487788 C 1.816674145 0.485612775 -0.711306139 C 1.921297908 -0.847467485 -0.121006850 C 0.831421423 -1.503284918 0.280113784 C -0.536807011 -0.902465705 0.115376352 C -0.487195770 0.614461273 0.084129015 H 0.605476050 2.178726401 -1.032393867 H 2.685741577 0.916348364 -1.188332892 H 2.896862285 -1.306444904 -0.039426378 H 0.909329476 -2.507239629 0.675871028 H -0.968896393 -1.274964444 -0.823044291 H -1.203307132 -1.239489077 0.909995804 H -1.438667507 1.064451464 -0.187904792 H -0.349596583 0.962674130 1.240637617 H -0.264145581 1.161127199 2.332171813

=============================== C6H7 E=-6333.538

=============================== C 0.651861990 1.202524824 -0.492693500 C 1.876171897 0.500690771 -0.586287995 C 1.915241765 -0.872823463 -0.251046231 C 0.803176211 -1.534298266 0.152381854 C -0.528226767 -0.864070006 0.262886585 C -0.488575979 0.586054720 -0.097024636 H 0.627593948 2.254599533 -0.745364748 H 2.773451329 1.009883418 -0.903406730 H 2.855286089 -1.404830201 -0.318629173 H 0.858860060 -2.585468186 0.403052464 H -1.262606717 -1.386347796 -0.368763708 H -0.928586490 -0.987897748 1.279772708 H -1.412415383 1.145721582 -0.032295356

=============================== C6H6 E=-6318.893

=============================== C 0.641242133 1.167230785 -0.553704142 C 1.850923921 0.487760099 -0.599882584 C 1.914314103 -0.843791469 -0.212407031 C 0.768346848 -1.495901163 0.221402627 C -0.442059270 -0.817431512 0.264891033 C -0.505398221 0.514255271 -0.122234591 H 0.592489430 2.205023462 -0.850869933 H 2.742790946 0.994263730 -0.939994248 H 2.856525281 -1.372563012 -0.247788017 H 0.818365992 -2.532152588 0.525221690 H -1.333388271 -1.323760162 0.606640584

15

H -1.448709749 1.040628282 -0.094698914 ===============================

C6H5 E=-6300.225 ===============================

C 0.647242635 1.166016902 -0.556431659 C 1.868075616 0.493138954 -0.604382031 C 1.868631640 -0.819072073 -0.209005252 C 0.770799414 -1.514219383 0.226266674 C -0.440456594 -0.823310740 0.266436733 C -0.496862320 0.509153505 -0.122240260 H 0.596516251 2.203500673 -0.857932102 H 0.831636489 -2.551307168 0.526500203 H -1.334381753 -1.329383143 0.604494710 H -1.438567657 1.037916252 -0.089878153 H 2.766521719 0.992241504 -0.939578076

=============================== TS C6H5+C2H4->C6H5C2H4 E=-8438.116

=============================== C 2.304410539 0.409837024 0.288647848 C 3.204626636 -0.490559119 -0.226296806 C 5.393579917 0.252957557 -0.476388868 H 5.533769909 -0.544411401 -1.193059785 C 5.964668459 0.204210137 0.735266846 H 6.462414685 -0.687726027 1.087529718 H 5.901212850 1.037367124 1.420624636 H 4.974073172 1.172960315 -0.859510334 C 2.891562139 -1.783048620 -0.567449843 C 1.572102598 -2.196145513 -0.391315847 C 0.627552619 -1.314590579 0.118884452 C 0.988352197 -0.016390881 0.458926423 H 2.599870808 1.415897711 0.557122463 H 3.635230921 -2.464180774 -0.959394685 H 1.285021822 -3.206244040 -0.650715457 H -0.393590023 -1.641211376 0.255467424 H 0.248554858 0.664379378 0.858725745

=============================== C6H5C2H4 E=-8439.893

=============================== C 0.700035622 1.181965580 -0.519418377 C 1.879132301 0.451089869 -0.589716844 C 1.847469352 -0.898816120 -0.243518265 C 0.666814851 -1.500189546 0.160094532 C -0.506517421 -0.758492346 0.227148367 C -0.486537846 0.584200265 -0.113355593 H 0.707924352 2.232307974 -0.781345769 C 3.172118839 1.087023522 -1.047066291 H 2.762637372 -1.475764713 -0.287896857 H 0.659481416 -2.548435045 0.424650883 H -1.427790359 -1.225735414 0.544620350 H -1.392315848 1.172026343 -0.059944177 C 4.315322968 0.831733545 -0.127103642 H 3.008794604 2.164784689 -1.164481796 H 3.422781248 0.718141480 -2.043770678 H 5.329269043 0.819048582 -0.492716829 H 4.156928324 0.838856263 0.939318676

===============================

16

TS C6H5C2H4+C2H4->C6H5C4H8(C4H8 chain) E=-10577.646 ===============================

C 0.157631132 0.107325565 -0.451624662 C 1.112524731 -0.177641618 0.520093990 C 2.518221036 0.371482966 0.406472205 C 3.393946505 -0.570906570 -0.367301381 H 2.926337781 0.527309706 1.406686278 H 2.485418031 1.344435250 -0.087509355 C 5.385211061 0.475243299 -0.445513540 H 3.192669156 -0.669091211 -1.425715636 H 3.681421732 -1.491245313 0.123090564 H 4.892555455 1.305688421 -0.933416482 C 6.293713674 -0.267300551 -1.114424622 H 6.403928201 -0.190034234 -2.186327799 H 6.898758197 -1.005836883 -0.608851747 H 5.383867074 0.493533601 0.636176619 C 0.761430713 -1.019362829 1.571762014 C -0.513588849 -1.558348813 1.655260759 C -1.458619029 -1.265121302 0.682079168 C -1.118869432 -0.429678374 -0.372532460 H 0.415623146 0.762387731 -1.274313275 H 1.493542463 -1.248011176 2.336100912 H -0.771573276 -2.204079368 2.483100137 H -2.453833228 -1.681031718 0.747662899 H -1.850298255 -0.191673793 -1.132332262

=============================== C6H5C4H8(C4H8 chain) E=-10579.07

=============================== C 0.932031244 1.161708782 -0.194644603 C 1.903117506 0.316189625 -0.724902406 C 1.662617299 -1.054162412 -0.718220631 C 0.481680146 -1.568103064 -0.202353363 C -0.479690825 -0.714563466 0.318994862 C -0.250784726 0.654360421 0.321526844 H 1.103598568 2.230947295 -0.195304941 C 3.208579733 0.869119745 -1.226220621 H 2.406959993 -1.726061319 -1.127090768 H 0.310388263 -2.635559865 -0.212373762 H -1.402451403 -1.112698991 0.716198295 H -0.996930497 1.327464780 0.720298673 C 4.266699474 0.923844385 -0.122336800 H 3.054903584 1.873924731 -1.625073461 H 3.581266995 0.253739597 -2.047992148 C 5.600960995 1.497504685 -0.628145706 H 4.429969233 -0.079357524 0.276339027 H 3.898249725 1.532854182 0.705457280 C 6.638039540 1.549188574 0.435115403 H 5.418598497 2.498216446 -1.026457112 H 5.945365047 0.880907504 -1.462248828 H 7.233099597 0.679892709 0.666910827 H 6.724879156 2.407068078 1.082907833

=============================== TS C6H5C4H8(C4H8 chain)->C6H5C4H8(ring) E=-10578.491

=============================== C 0.887465129 0.876195210 -1.101750486 C 1.927375471 0.664826749 -0.222302337

17

C 1.885852292 -0.473319716 0.626119631 C 0.695828993 -1.232546842 0.699497601 C -0.331139906 -0.995814288 -0.191098010 C -0.238530910 0.049552858 -1.105868945 H 0.946916052 1.700107716 -1.802446733 C 3.191013937 1.478501466 -0.258494501 H 0.615625782 -2.028863129 1.425883084 H -1.219713060 -1.611173916 -0.166344290 H -1.042254910 0.236526095 -1.803402613 C 4.438184792 0.578366051 -0.310052014 H 3.250076860 2.136214427 0.612549415 H 3.171233435 2.122084909 -1.138994881 C 4.193161084 -0.649429713 -1.194392145 H 4.704458887 0.242078055 0.693927188 H 5.285811788 1.155414436 -0.678534131 C 3.273224913 -1.639838250 -0.533225059 H 5.149725899 -1.128227967 -1.424604799 H 3.769953528 -0.322488860 -2.145861385 H 3.706442543 -2.235980610 0.262676958 H 2.578261515 -2.180893770 -1.161566387 H 2.574756527 -0.515370333 1.460279446

=============================== C6H5C4H8(ring) E=-10579.328

=============================== C 0.625027222 1.147359206 -0.676927094 C 1.864976730 0.631301909 -0.475928743 C 2.055736092 -0.705133996 0.185609361 C 0.778547338 -1.464261216 0.346297509 C -0.431890982 -0.903476135 0.116386326 C -0.544128707 0.426175918 -0.354780088 H 0.531078263 2.125614432 -1.133824548 C 3.120587508 1.312813036 -0.954638996 H 0.849778869 -2.485592697 0.699107213 H -1.330332359 -1.483410036 0.279320755 H -1.515941926 0.863596603 -0.523625422 C 4.353808729 0.750173932 -0.254025701 H 3.041577716 2.391372187 -0.812538463 H 3.226544369 1.150787185 -2.033485739 C 4.501652606 -0.755908962 -0.521443502 H 4.261570509 0.929395690 0.818352717 H 5.251224538 1.275565170 -0.577825147 C 3.143382221 -1.483847872 -0.577443970 H 5.127742249 -1.194579815 0.255592996 H 5.028825000 -0.907235057 -1.463603949 H 2.806985840 -1.590464007 -1.609716236 H 3.231027182 -2.491160874 -0.170764881 H 2.466232063 -0.532113381 1.197037790

=============================== C6H4C4H8(ring) E=-10564.754

=============================== C 0.656580160 1.205041334 -0.429214264 C 1.841858115 0.531355003 -0.684609016 C 1.928566320 -0.839308382 -0.424437698 C 0.826975977 -1.511610452 0.083894640 C -0.360832615 -0.834777155 0.327947045 C -0.446384213 0.524865758 0.070767384

18

H 0.594567330 2.268553764 -0.621631963 C 3.091859546 1.200163970 -1.179014607 H 0.896821853 -2.572322702 0.289360795 H -1.214466290 -1.367826345 0.722234192 H -1.366299680 1.057464589 0.266598618 C 4.260997733 0.829419383 -0.254906583 H 2.961249453 2.280085633 -1.223608790 H 3.315791513 0.860620814 -2.194429323 C 4.413016326 -0.701212762 -0.087343576 H 4.070271141 1.286276615 0.715490525 H 5.184762655 1.266505545 -0.630532474 C 3.248711428 -1.490467111 -0.713192828 H 4.472123094 -0.945075770 0.972050480 H 5.345032271 -1.042091395 -0.536257217 H 3.393212378 -1.520878280 -1.796717817 H 3.258054706 -2.523309943 -0.368134735

=============================== TS C6H5C4H8+H->C6H5C4H7+H2 E=-10578.017

=============================== C 0.619453541 1.195922060 -0.433972472 C 1.876784751 0.596472306 -0.436571144 C 1.965969438 -0.787420129 -0.260688662 C 0.797185314 -1.531592974 -0.088954012 C -0.444526503 -0.925642066 -0.094068818 C -0.534261438 0.450753118 -0.267272011 H 0.551842824 2.269890230 -0.555893927 C 3.113800240 1.445875712 -0.617433340 H 0.874424588 -2.604301212 0.037405114 H -1.338504787 -1.519097350 0.035121978 H -1.498665568 0.938741136 -0.266217642 C 4.382363559 0.746840045 -0.142629670 H 2.976146943 2.392449595 -0.093940112 H 3.220835605 1.691505213 -1.678119354 C 4.449096966 -0.651264150 -0.753283375 H 4.375870881 0.665561101 0.946583201 H 5.260062810 1.330034092 -0.420333773 C 3.283971115 -1.476970958 -0.256913191 H 5.391220360 -1.144690371 -0.519978013 H 4.391940668 -0.561501464 -1.841679880 H 3.174478863 -2.442348837 -1.046514152 H 3.482161836 -1.997509954 0.679522367 H 3.088937850 -3.202124684 -1.712475511

=============================== C6H5C4H7(ring) E=-10547.255

=============================== C 0.631201907 1.161668110 -0.623763630 C 1.869795759 0.549842473 -0.595703864 C 1.968742158 -0.806055582 -0.183200132 C 0.782650302 -1.486716459 0.174298001 C -0.441024459 -0.856552469 0.132925166 C -0.525423803 0.476295309 -0.264520282 H 0.563641361 2.196867258 -0.934750817 C 3.120897325 1.274695702 -1.016918691 H 0.852646740 -2.519067424 0.491137114 H -1.334782020 -1.395895991 0.413190680 H -1.482218025 0.977165563 -0.293832213

19

C 4.337101227 0.780449017 -0.238604672 H 2.985601149 2.348541469 -0.890489983 H 3.293736967 1.101224454 -2.084124582 C 4.497164395 -0.727052314 -0.427103082 H 4.197836311 0.996836887 0.821979105 H 5.236836038 1.300553342 -0.565261360 C 3.223059957 -1.445412426 -0.128798712 H 5.300579498 -1.113408254 0.201897564 H 4.803535428 -0.927766867 -1.461988692 H 3.257577470 -2.496932557 0.120191466

=============================== C6H4C4H6(ring) E=-10531.637

=============================== C 0.630456607 1.195536436 -0.477663609 C 1.862192077 0.566505581 -0.566057805 C 1.954855682 -0.804108411 -0.286440225 C 0.808353371 -1.509895935 0.064577315 C -0.419515147 -0.870965589 0.150977877 C -0.508889135 0.486099018 -0.118042646 H 0.558686180 2.253625494 -0.695686127 C 3.105173891 1.290163512 -1.017271082 H 0.885364587 -2.567641976 0.280495321 H -1.301551207 -1.429783913 0.429290065 H -1.460857753 0.993280568 -0.049438334 C 4.351410105 0.764349004 -0.309970662 H 2.994061496 2.362821649 -0.864327814 H 3.221834585 1.128281195 -2.093541661 C 4.392390772 -0.739837818 -0.354767961 H 4.347522823 1.085702144 0.737262805 H 5.247882558 1.186744598 -0.761200326 C 3.269305428 -1.453076040 -0.347618342 H 5.353174798 -1.236835838 -0.354459821 H 3.302928998 -2.534840592 -0.341166978

=============================== TS C6H4C4H6+H->C6H4C4H5+H2 E=-10544.88

=============================== C 0.623964159 1.197279439 -0.485831474 C 1.868414632 0.578602785 -0.503042629 C 1.957943346 -0.796462917 -0.235494056 C 0.800386009 -1.510578329 0.057319445 C -0.435249339 -0.881973507 0.080178149 C -0.523968069 0.476270234 -0.194124815 H 0.556249379 2.253578435 -0.713094150 C 3.089387430 1.304837353 -0.916366288 H 0.873115099 -2.570230570 0.265152953 H -1.326493817 -1.449894671 0.305726718 H -1.484575617 0.971466905 -0.186856817 C 4.400754483 0.750282907 -0.396390289 H 3.003659457 2.383356575 -0.805003083 H 3.140649643 1.163933147 -2.123297998 C 4.399188850 -0.751489556 -0.362378337 H 4.589302830 1.125599557 0.616736522 H 5.224879782 1.115477402 -1.010791177 C 3.268482030 -1.448137833 -0.282121177 H 5.353059148 -1.262261297 -0.356319915 H 3.294938228 -2.528670493 -0.221711775

20

H 3.250490609 1.039112621 -3.201082986 ===============================

C6H4C4H5 E=-10514.125 ===============================

C 0.604903453 1.213347256 -0.419541378 C 1.887502297 0.611717960 -0.400733896 C 1.963133662 -0.802706616 -0.226171534 C 0.796972480 -1.539844119 -0.082264706 C -0.447512917 -0.927280885 -0.105210531 C -0.534051276 0.458212461 -0.275044704 H 0.536545211 2.285194887 -0.550426782 C 3.056955888 1.357069081 -0.547785596 H 0.868782078 -2.611510039 0.051445981 H -1.344843093 -1.517492865 0.008607505 H -1.502245996 0.938492006 -0.292643420 C 4.415408148 0.748233835 -0.539471876 H 2.981611138 2.428820848 -0.675939035 C 4.399820173 -0.736658681 -0.350037646 H 5.033062453 1.210157471 0.244016171 H 4.946312725 0.995784845 -1.469798617 C 3.273032070 -1.431231367 -0.199983818 H 5.356122458 -1.243035871 -0.315366718 H 3.312281123 -2.504797201 -0.063334644

=============================== C10H8 E=-10499.312

=============================== C 0.634297974 1.210494386 -0.472548319 C 1.905669620 0.586967744 -0.456991217 C 1.984696172 -0.802607188 -0.187087549 C 0.789640314 -1.522512154 0.055265197 C -0.421582847 -0.893370733 0.037963685 C -0.500230237 0.492020933 -0.228300770 H 0.578339637 2.272491452 -0.672595006 C 3.099752054 1.304995761 -0.706714683 H 0.853643319 -2.583260465 0.259367138 H -1.326583547 -1.453433076 0.226048869 H -1.464663088 0.979610835 -0.240824030 C 4.312753181 0.676518040 -0.683526313 H 3.038160209 2.365032333 -0.912491576 C 4.391472689 -0.708573203 -0.420960993 H 5.215077554 1.235444103 -0.885959799 C 3.254667024 -1.427844165 -0.182304739 H 5.354659383 -1.197896248 -0.409704085 H 3.311689400 -2.487480327 0.027318893

=============================== C4H6 E=-4243.976

=============================== C -0.205090833 0.432085995 0.014562284 C 0.914079889 -0.281470896 0.067468367 H -0.421643711 1.085137281 -0.817632535 H 1.635546666 -0.214427418 -0.739618156 H -0.937579538 0.379234901 0.809711357 C 1.250525331 -1.176141617 1.168987061 C 2.368172405 -1.890929662 1.225318263 H 0.527429668 -1.241461160 1.974907772 H 3.104187537 -1.842100737 0.433163374

21

H 2.581778151 -2.543177317 2.059083940 ===============================

TS C4H6+H->C4H5+H2 E=-4256.738 ===============================

C -0.234994574 0.421285749 0.060699115 C 0.898295494 -0.271736368 0.067314429 H -0.486239119 1.084544380 -0.754100311 H 1.596007373 -0.179510759 -0.756840018 H -0.943927729 0.342224031 0.874833272 C 1.277468935 -1.181148902 1.150887932 C 2.397641193 -1.875256476 1.171832496 H 0.575686897 -1.271396587 1.975571423 H 3.204339468 -1.914987303 0.452622902 H 2.598900913 -2.713545117 2.314278846 H 2.673297575 -3.202267456 3.022534903

=============================== C4H5 E=-4225.305

=============================== C -1.061006615 0.688490901 -0.152977316 C 0.064437292 0.165940320 0.320812870 H -1.170962174 1.758224714 -0.281223988 H -1.901011926 0.065742685 -0.425179145 C 1.228711219 0.971938718 0.702672454 C 2.344516680 0.466607959 1.171366000 H 2.705391821 -0.526205540 1.389662891 H 0.158605906 -0.907157772 0.443268974 H 1.133153988 2.048260926 0.579439721

=============================== TS C4H5+C2H4->C6H9(chain) E=-6363.209 ===============================

C -1.454022926 -0.508600797 -0.188383672 C -0.872627434 0.651245417 0.012746831 C -2.889582156 -0.682113815 -0.417272581 H -0.844966916 -1.409890546 -0.187787310 H -1.251622617 1.662055724 0.058643407 C 1.415930142 0.611126957 0.346066866 C 1.811608461 -0.669705075 0.268492066 H 1.239285052 1.078812964 1.304648329 H 1.507783365 1.271246110 -0.505180710 H 2.094219372 -1.114843271 -0.674927543 H 1.824571099 -1.308260186 1.140364523 C -3.458700766 -1.866073876 -0.613896150 H -4.521646495 -1.961225143 -0.780052386 H -2.870487812 -2.774749831 -0.613264957 H -3.494110623 0.217366358 -0.421195880

=============================== C6H9(chain) E=-6364.995

=============================== C 2.367329213 0.443076768 0.221018818 C 3.407602513 -0.386013121 0.244670335 C 0.991774570 0.028908906 0.462350476 C 4.830384543 0.018704809 -0.008606616 H 3.237178418 -1.440216179 0.442982874 H 4.863939208 1.104259988 -0.167383843 C 5.426086457 -0.702658087 -1.169772988 H 6.478432522 -0.935566967 -1.200915418

22

H 4.835985514 -0.871327387 -2.057119245 H 5.431929210 -0.175419877 0.883476480 C -0.043916546 0.861826630 0.455169290 H 0.831578205 -1.025590606 0.659548127 H -1.050096487 0.516082549 0.640875302 H 0.090902766 1.918671293 0.262646993 H 2.529765543 1.497294264 0.015375821

=============================== TS C6H9(chain)->C6H9(ring) E=-6364.513 ===============================

C 0.576754848 0.948500998 -0.786774539 C 1.591394496 0.330740584 -0.138695812 C 1.504977678 -1.071409925 0.221463712 C 0.345320942 -1.694536789 0.469380314 C -1.027554114 -1.062518284 0.517874378 C -1.059612465 0.411981424 0.771685673 H 0.589714699 2.017323764 -0.949558269 H -0.110908018 0.380679876 -1.396993622 H 2.423532524 0.910005857 0.241901881 H 2.425613473 -1.631231015 0.337304993 H 0.376603740 -2.750156933 0.710781131 H -1.569230781 -1.292912363 -0.404586708 H -1.586771619 -1.572101113 1.311331550 H -1.907581880 0.981497661 0.419379640 H -0.574933291 0.782327145 1.662676802

=============================== C6H5C2H3 E=-8424.76

=============================== C 1.001351496 1.133884415 -0.211067412 C 1.951301753 0.240557106 -0.704225285 C 1.637765009 -1.120253865 -0.708724992 C 0.415070094 -1.565889660 -0.238878837 C -0.522916311 -0.662866056 0.248524050 C -0.224985783 0.690612466 0.260734539 H 1.230309124 2.191685660 -0.200436804 C 3.237363784 0.768127602 -1.185810680 H 2.352217950 -1.839837181 -1.083176956 H 0.190235196 -2.623377602 -0.251925224 H -1.477032248 -1.014740332 0.614288762 H -0.946061701 1.402929088 0.636313417 C 4.248831616 0.068590531 -1.688643924 H 3.343310430 1.844873347 -1.110388590 H 5.152801741 0.563197854 -2.012212049 H 4.215149716 -1.006773125 -1.795400447

=============================== TS C6H5C2H3+H->C6H5C2H2+H2 E=-8437.537

=============================== C 1.022087154 1.143166945 -0.218115779 C 1.948830063 0.221384933 -0.701124516 C 1.606669460 -1.131823820 -0.695930146 C 0.375016678 -1.545736396 -0.221682814 C -0.541301213 -0.616242928 0.257698735 C -0.213565458 0.730285604 0.257921577 H 1.275044285 2.195304888 -0.216617452 C 3.250955472 0.710949654 -1.197353488 H 2.309360405 -1.865496400 -1.065359964

23

H 0.125529506 -2.597602786 -0.224463284 H -1.502833615 -0.942613522 0.627725540 H -0.918604479 1.461066615 0.628391891 C 4.235683733 -0.010315306 -1.689194238 H 3.388829386 1.787712847 -1.140762769 H 5.392457211 0.725167888 -2.097861614 H 4.342064539 -1.073236360 -1.847733945 H 6.063697546 1.214310611 -2.328736118

=============================== C6H5C2H2 E=-8406.156

=============================== C 0.978862773 1.140419235 -0.202740866 C 1.943776776 0.266785906 -0.696740327 C 1.664881774 -1.101280598 -0.717134585 C 0.451629319 -1.576927014 -0.255382999 C -0.506063032 -0.695835201 0.236091966 C -0.238985464 0.663639708 0.260795965 H 1.185306345 2.202559738 -0.182835383 C 3.229648191 0.795877595 -1.179299890 H 2.410957941 -1.785494084 -1.099745523 H 0.248301930 -2.638419278 -0.276861627 H -1.453574888 -1.070161599 0.596431836 H -0.977714107 1.355360057 0.640375266 C 4.217390179 0.089225717 -1.667815618 H 3.353586228 1.878195338 -1.115866917 H 5.199214376 0.301719114 -2.055183240

=============================== TS C6H5C2H2+C2H4->C6H5C4H6(C4H6 chain) E=-10543.972

=============================== C 1.059896408 1.130470190 -0.465912755 C 2.011582776 0.148636210 -0.734772451 C 1.661959011 -1.187827309 -0.538684005 C 0.401894717 -1.527763253 -0.079482252 C -0.537161524 -0.539366989 0.191275078 C -0.203605336 0.791719386 -0.004448818 H 1.315587760 2.171015122 -0.618016487 C 3.349355730 0.552475294 -1.218039678 H 2.379345377 -1.965939602 -0.759021625 H 0.146311478 -2.568540328 0.062390767 H -1.521899229 -0.807784784 0.546185779 H -0.927519439 1.568141583 0.199735232 C 4.416303932 -0.207865940 -1.297746442 H 3.432093220 1.596730416 -1.512673648 C 6.335479910 0.700944103 -2.195715554 H 4.607621403 -1.244625437 -1.071642801 C 6.758472481 -0.104756283 -3.183430834 H 6.782213768 0.655018396 -1.212500669 H 5.737570201 1.575290093 -2.412149103 H 6.389468598 0.002444984 -4.193006915 H 7.446578665 -0.915640835 -2.991994429

=============================== C6H5C4H6(C4H6 chain) E=-10545.767

=============================== C 1.005406264 1.113108335 -0.581569542 C 2.017791132 0.160805512 -0.697000382 C 1.712255723 -1.166384453 -0.386649864

24

C 0.439319909 -1.522998349 0.020497594 C -0.560139089 -0.563128757 0.128597277 C -0.271544685 0.758094601 -0.173894700 H 1.226041078 2.146430441 -0.816399053 C 3.351827414 0.591682084 -1.136944821 H 2.474613413 -1.928093029 -0.461673003 H 0.223847925 -2.555706384 0.256649626 H -1.553323940 -0.845200037 0.447427834 H -1.039453273 1.514577329 -0.092743961 C 4.418318757 -0.176606881 -1.331665779 H 3.452149663 1.657526722 -1.320532552 C 5.756240184 0.337279581 -1.805199643 H 4.361887879 -1.247085029 -1.172277702 C 6.110853922 -0.256701293 -3.128755543 H 6.523412861 0.088076973 -1.070285540 H 5.708203425 1.425736504 -1.874712627 H 5.586239487 0.064726682 -4.014717599 H 6.738715181 -1.130630255 -3.197070111

=============================== TS C6H5C4H6(C4H6 chain)-> C6H5C4H6(ring) E=-10545.273

=============================== C 1.227780484 1.135678155 -0.169571993 C 1.876768040 0.284084602 -1.051751948 C 1.471412136 -1.073270759 -1.129036075 C 0.392112242 -1.511253857 -0.334681414 C -0.203602751 -0.656023249 0.567807538 C 0.202476847 0.676660672 0.646928411 H 1.551218098 2.166579909 -0.101957631 C 3.079328864 0.707648936 -1.768079751 H 1.732478284 -1.640112118 -2.013021262 H 0.039688146 -2.528758491 -0.431649601 H -1.011751326 -1.009946913 1.192670288 H -0.282844837 1.351717587 1.336816685 C 4.118213816 -0.097260128 -1.996595673 H 3.136879584 1.742549290 -2.085032541 C 4.259712483 -1.518142867 -1.505956034 H 4.967499529 0.300749445 -2.538420626 C 3.348460732 -1.887612079 -0.375054232 H 5.301917713 -1.652603784 -1.193270355 H 3.119237158 -2.935271548 -0.233559387 H 3.431225314 -1.310942112 0.536688460 H 4.121402158 -2.210331588 -2.341864022

=============================== C6H5C4H6(ring) E=-10546.452

=============================== C 0.921292592 1.203813548 -0.235175004 C 1.816260209 0.351227415 -0.843702870 C 1.544510398 -1.126851493 -0.919218288 C 0.405515904 -1.557913145 -0.051627571 C -0.416242399 -0.676574007 0.551313688 C -0.201785459 0.729119033 0.435039984 H 1.125183223 2.267373625 -0.249948930 C 3.044378350 0.811931727 -1.435136254 H 1.272571532 -1.354431071 -1.965204071 H 0.235406739 -2.622636980 0.051135704 H -1.247718858 -1.033730392 1.143729648

25

H -0.882219142 1.418100616 0.911908548 C 3.999153329 -0.031440141 -1.857755557 H 3.188615206 1.881144806 -1.533572696 C 3.904125449 -1.520635055 -1.684218086 H 4.891984612 0.362992346 -2.324988946 C 2.843989367 -1.904428058 -0.655408521 H 3.671526642 -1.986564117 -2.647651647 H 3.196622484 -1.660354809 0.347926538 H 2.649064529 -2.976658831 -0.686284709 H 4.877703313 -1.914199973 -1.388496054

=============================== TS C6H5+C2H4->C6H6+C2H3 E=-8437.695 ===============================

C 0.694380520 1.159833168 -0.458197951 C 1.902715449 0.475143446 -0.546290362 C 1.917152206 -0.871495429 -0.248286242 C 0.786433429 -1.562096080 0.134973067 C -0.416947373 -0.868294773 0.220146923 C -0.459884002 0.487733987 -0.076805345 H 0.655032891 2.216147610 -0.687094978 H 0.832360907 -2.618451161 0.363429183 H -1.318691757 -1.386325069 0.517231206 H -1.396622183 1.023053020 -0.010656260 H 2.807383277 0.989878305 -0.840359739 H 3.071979024 -1.541797368 -0.326575925 C 4.195277590 -2.221979221 -0.273899872 C 4.697776587 -2.425537786 0.921939896 H 5.615950182 -2.984221898 1.070258221 H 4.210345222 -2.038267083 1.808898274 H 4.589871315 -2.557266841 -1.223963874

=============================== C3H8 E=-3241.177

=============================== C -0.168535205 0.403497997 0.016244457 C 1.148656740 -0.362859572 -0.017899599 H -1.026479099 -0.266429065 0.058003325 H -0.273120244 1.029168649 -0.871132646 H 1.161958925 -1.028534611 -0.882326609 C 2.350155575 0.575053991 -0.075122239 H -0.210490600 1.058329048 0.887637004 H 1.223388807 -1.001092556 0.863940243 H 3.291119640 0.026721558 -0.100680151 H 2.367970554 1.232744136 0.795018686 H 2.304833242 1.206286847 -0.963701237

=============================== C3H6 E=-3207.719

=============================== C -0.251077032 0.493894171 -0.038628060 C 0.966771097 -0.357698978 0.143017552 H -0.772202191 0.234840233 -0.961561941 H 0.020002332 1.548351330 -0.111854144 H 1.711217290 -0.308004017 -0.644842583 H -0.942372856 0.372763043 0.793756378 C 1.186431101 -1.148044163 1.180676631 H 2.086059673 -1.741592335 1.260209415 H 0.469112248 -1.227049766 1.988305044

26

=============================== C3H7 E=-3222.912

=============================== C -0.249641192 0.501273116 -0.070604909 C 1.038951159 -0.332937042 0.044039963 H -1.125187902 -0.147033927 -0.065544781 H -0.257340096 1.082569041 -0.992479185 H 1.109310248 -0.986015543 -0.828130317 H 1.898150266 0.338151751 0.009014232 H -0.336425084 1.187662178 0.770781369 C 1.073395486 -1.143124254 1.291371371 H 0.508238626 -2.060324950 1.360562081 H 1.464634202 -0.729576543 2.208037516

G4 calculations on conversion and product distributions at equilibrium

G4 (60, 61) calculations were carried out using the Gaussian 09 (62) suite of ab initio quantum chemistry programs. The free energies of CH4, C2H4, C6H6 and C10H8 at 1225K

(952 C) and 1363K (1090 C) were computed. The conversions of CH4 as well as the distribution of C2H4, C6H6 and C10H8 at equilibrium condition were calculated using

K = exp (-G/RT)

where K is the equilibrium constant, and G is the free energy change of the reaction at the given temperature.

The reactions taken into account here are: CH4 = 1/2C2H4 +H2

CH4 = 1/6C6H6 + 3/2H2

CH4 =1/10 C10H8 + 8/5H2 The calculations were carried out at standard conditions, with a CH4 pressure of 1 atm

at the beginning of the reaction. The results are shown below. Our experimental conversions are significantly lower than those at equilibrium condition, which means that the reaction does not reach equilibrium under our experimental conditions, and product distributions are therefore controlled. Equilibrium conversion. 1363K 1225K CH4 C2H4 37.6% 23.1% CH4 C6H6 62.5% 43.9% CH4 C10H8 64.3% 45.5% CH4 C2H4 + C6H6 + C10H8 65.7% 46.9% CH4 C2H4 + C6H6 63.1% 44.3% Product distributions (mol %) at equilibrium. 1363K 1225K

CH4 C2H4 + C6H6 + C10H8 C2H4 11.9% C6H6 32.6% C10H8 55.5%

C2H4 9.0% C6H6 34.0% C10H8 57.0%

CH4 C2H4 + C6H6 C2H4 12.3% C6H6 87.7%

C2H4 9.7% C6H6 90.3%

27

Heat input for methane conversion

Since this process is endothermic, it requires heat input to maintain the conversion. The heat input to convert one mol CH4 was studied with G4 calculations in comparison to several typical pyrolysis processes (63-66) by assuming no energy loss during process. The results listed in Table S3 show that the present process is advantageous because the estimated heat input needed to convert one mol CH4 to 48% ethylene, 28% benzene and 24% naphthalene is about one half of that for the typical thermal pyrolysis with 95% acetylene selectivity and 2/3 of that for the process with 60% acetylene selectivity.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Methane Ethylene Benzene Naphthalene

Pro

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30

35

40

45

50

55

60

Met

han

e co

nve

rsio

n (

%)

Benzene

Pro

du

ct s

elec

tivi

ty (

%)

Reaction time (h)

Ethylene

Conversion

Naphth.

b

Fig. S1 Reproducibility of methane conversion over 0.5% Fe©SiO2 under different conditions, which have been repeated for more thanthree time, demonstrating very good reproducibility of the data: (a) methane conversion and product selectivities; (b) stability test at 1293 K and 14.5 L·gcat

-1·h-1.

29

1vol.% ethane 5vol.% ethane0

20

40

60

80

100

Co

nve

rsio

n &

sel

ecti

vity

(%

)

Ethane content (vol.%)

Methane conv. Ethane conv. Ethylene sel. Benzene sel. Naphthalene sel. Coke sel.

Fig. S2 Reaction results in the presence of 1 vol. % and 5vol. % of ethane in the feeding stream at 1173 K and 4.84 L·gcat

-1·h-1 over 0.5%Fe©SiO2.

30

Fe2O3

Fe2O3

Fe2O3

Fe2O3

Fe2O3

Fe2O3

31

Fe2O3

Fe2O3

Fe2O3

Fe2O3

Fe2O3

Fe2O3

32

Fe2O3

Fe2O3

Fe2O3

Fe2O3

33

Fe2O3

Fe2O3

Fe2O3

Fe2O3

34

Fig. S3 HR-TEM images of the fresh 0.5% Fe©SiO2 catalyst.

Fe3O4

Fe3O4

35

Fig. S4 TEM images for the 0.5% Fe/SiO2 catalyst: (a) fresh; and (b) after reaction at 1223 K and space velocity of 4.84 L·gcat

-1·h-1.

36

Fig. S5 (a) Free energy profile for the carburization of the isolated iron site as it evolves from 3Si-coordinated (structure (i)) to a Si-2C-coordinated (structure (ix)) configuration, followed by the activation of CH4 on the resulting structure; (b) structural configurations along the reaction coordinate.

37

Fig. S6a Schematic of the VUV-SPI-MBMS system coupled to a catalytic reactor.

38

Fig. S6b Schematic of the catalytic reactor.

39

Fig. S6c Analysis of the effluent generated in the reactor at a feed flow rate of 30 mL/min and 1253 K, using detection by VUV-SPI-MBMS, and showing a different set of species from Fig. 3b.

40

-0.87

0.0

0.87

1.74

-1.74

-2.61

 G (eV)

-0.23

-1.81

0.0

2.03*

-2.66

-2.01

-1.10*

2.47*

-0.87

0.7*0.62

-1.96

-0.39*2 CH3

C2H6

C2H5 + x

C2H4 + x

Fig. S7a Computed reaction profiles for 2CH3 C2H4 + H2. * The barrier is

estimated by assuming the barrier of AB A· + B· is equal to H for the reaction.

41

2+ + +

0.0

0.43

0.87

1.30

1.74

2.17

2.61

3.04

-0.43

-0.87

-1.30

0.31

2.10

1.02

2.62

0.80

2.85

0.85

2.37

0.0

-0.73

-1.02

2.35

0.14

 G (eV)

+ H2

+ H2

+ H2

+ 2 H2

+ H + 2 H2 Fig. S7b Reaction profiles for 3C2H4 C6H6 + 3H2. Note that all radical dehydrogenations are comprised of two elementary steps: C-H bond dissociation and H atom abstraction. C-H bond dissociation of radicals is always the easier of the two, and its barrier is not shown for clarity.

42

2+

0.0

0.43

0.87

1.30

1.74

2.17

2.61

3.04

-0.43

-0.87

-1.30

0.66

1.69

0.65

2.33

0.24

2.52

0.50

2.08

0.0

-1.00-1.14

1.73

0.02

2.26

-0.73

+

+

+

+

+ H2

+ H + 2 H2

+ H2 + H2

+ 2 H2

 G (eV)

Fig. S7c Reaction profiles for C6H6 + 2C2H4 C10H8 + 3H2. Note that all radical dehydrogenations are comprised of two elementary steps: C-H bond dissociation and H atom abstraction. The C-H bond dissociation (not shown) is facile for radicals.

43

Table S1 Reaction results of reference catalysts.

Catalysts Conversion

(%) Product selectivity (%)

Ethylene Ethane Benzene Naphthalene Coke SiO2 3.3 2.6 1.1 0 0 96.1

0.5Fe/SiO2a 4.4 1.9 0.8 0.1 0.4 96.5

0.5Fe/SiO2b 6.9 26.4 2.16 15.2 9.1 47.1

Reaction conditions: 1223 K and 4.84 L·gcat-1·h-1

a 0.5% Fe/SiO2 was subjected to leaching using aqueous HNO3 (0.5 mol/L), and then dried at 353 K for 12 h. b 0.5% Fe/SiO2 was calcined at 1973 K in He for 6 h, and subjected to leaching in aqueous HNO3 (0.5 mol/L), and then dried at 353 K for 12 h.

44

Table S2 EXAFS Fitting Parameters at the Fe – Edge.

Bond Length Shella

Fe-C Fe-Si Fe-O Fe-Fe

R (Å) b 1.6 2.4 2.000.03 2.460.01

2.840.01

R (Å)DFT 1.64 2.40 2.09 1.96

2.48 2.88

a The shells of Fe-C and Fe-Si are corresponding to Line 2 (Fig. 2c); the shells of Fe-O and Fe-Fe are corresponding to the reference Fe2O3 and Fe foil samples (Fig. 2c), respectively. b All results were obtained by phase shift correct.

45

Table S3 The heat input for converting 1 mol CH4 following our process incomparison with typical thermal pyrolysis processes.a

a G4 was used for transformation to hydrocarbons and DFT (M06-2x/cc-Pvtz) for coke, which was modeled as a polycyclic aromatic C54H18 for simplicity. b The effluent composition from Huels process (mol%): 16.4% CH4, 14.5% C2H2, 0.9% C2H4, 0.3% C6H6, 0.45% C3, 0.73% C4, 63.4% H2 and carbon black. (66)

Temperature (K)

Product selectivities (%) Heat input (kJ/mol CH4) Ethylene Acetylene Benzene Naphthalene Coke

1363 (this work)

48 0 28 24 0 104.3

1673 (63) ~8 ~60 ~2 -- 30 160.5 2273 (64) 0 95 -- -- 2.7 192.8

2148 b -- 73 -- -- ~3 172.8 773 (65) -- -- -- -- 100 92.59

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