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From Helical to Planar Chirality by On-Surface Chemistry

Oleksandr Stetsovych,1 Martin Švec,1 Jaroslav Vacek,2 Jana Vacek Chocholoušová,2 Andrej Jančařík,2 Jiří Rybáček,2 Krzysztof Kosmider,1 Irena G. Stará,2 Pavel Jelínek,1† Ivo Starý2†

1Institute of Physics of the CAS, Cukrovarnická 10, 162 00 Prague 6, Czech Republic. 2Institute of Organic Chemistry and Biochemistry CAS, Flemingovo nám. 2, 166 10 Prague 6,

Czech Republic.

Supplementary Information

From helical to planar chirality by on-surface chemistry

© 2016 Macmillan Publishers Limited, part of Springer Nature. All rights reserved.

SUPPLEMENTARY INFORMATIONDOI: 10.1038/NCHEM.2662

NATURE CHEMISTRY | www.nature.com/naturechemistry 1

http://dx.doi.org/10.1038/nchem.2662

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Computational details

The geometries of all reactants and products were first optimized in vacuo at the b97d1 and b3lyp2 levels of DFT theory with the cc-pVDZ.3 The transition state (TS) structures were then localized in

vacuo at the same levels using the QST3 algorithm. The Gaussian094 program was used for all aperiodic DFT calculations. The resulting minima and TS structures were then placed on a periodic Ag(111) surface and reoptimized using the nudged elastic band (NEB) algorithm5 as implemented in the QuantumWise Atomistix 10.8 toolkit.6 The GGA7/PBE8 functional with the DZP9 basis set was used throughout the periodic DFT calculations. In order to check a validity of way to describe van der Waals (VdW) interactions the selected systems were recalculated using Tkatchenko-Scheffler method (VdW-TS)10 as implemented in FHI-AIMS code11 in which all-electron electronic structure is described using DFT in a basis of numeric atom-centered orbitals (NAO). The calculations in vacuo and at the Ag(111) substrate were performed with the b3lyp2 and PBE8 exchange-correlation functionals 1 S. Grimme, Semiempirical GGA-type density functional constructed with a long-range dispersion correction, J. Comp. Chem. 27 1787–1799 (2006). 2 P. J. Stephens, F. J. Devlin, C. F. Chabalowski, M. J. Frisch, Ab Initio Calculation of Vibrational Absorption and Circular Dichroism Spectra Using Density Functional Force Fields, J. Phys. Chem. 98, 11623–11627 (1994). 3 T. H. D. Jr, Gaussian basis sets for use in correlated molecular calculations. I. The atoms boron through neon and hydrogen, J. Chem. Phys. 90, 1007–1023 (1989). 4 www.gaussian.com; Gaussian 09, Revision D.01, M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. Scuseria, M. A. Robb, J. R. Cheeseman, G. Scalmani, V. Barone, B. Mennucci, G. A. Petersson, H. Nakatsuji, M. Caricato, X. Li, H. P. Hratchian, A. F. Izmaylov, J. Bloino, G. Zheng, J. L. Sonnenberg, M. Hada, M. Ehara, K. Toyota, R. Fukuda, J. Hasegawa, M. Ishida, T. Nakajima, Y. Honda, O. Kitao, H. Nakai, T. Vreven, J. A. Montgomery, Jr., J. E. Peralta, F. Ogliaro, M. Bearpark, J. J. Heyd, E. Brothers, K. N. Kudin, V. N. Staroverov, R. Kobayashi, J. Normand, K. Raghavachari, A. Rendell, J. C. Burant, S. S. Iyengar, J. Tomasi, M. Cossi, N. Rega, J. M. Millam, M. Klene, J. E. Knox, J. B. Cross, V. Bakken, C. Adamo, J. Jaramillo, R. Gomperts, R. E. Stratmann, O. Yazyev, A. J. Austin, R. Cammi, C. Pomelli, J. W. Ochterski, R. L. Martin, K. Morokuma, V. G. Zakrzewski, G. A. Voth, P. Salvador, J. J. Dannenberg, S. Dapprich, A. D. Daniels, Ö. Farkas, J. B. Foresman, J. V. Ortiz, J. Cioslowski, D. J. Fox, Gaussian, Inc., Wallingford CT, 2009. 5 (a) H. Jónsson, G. Mills, K. W. Jacobsen, in Classical and Quantum Dynamics in Condensed Phase Simulations, B. J. Berne, G. Ciccotti, D. F. Coker, Eds. (World Scientific, Singapore, 1998), pp. 385–404; (b) G. Henkelman, H. Jónsson, Improved tangent estimate in the nudged elastic band method for finding minimum energy paths and saddle points, J. Chem. Phys. 113, 9978–9985 (2000); (c) G. Henkelman, G. Jóhannesson, H. Jónsson, in Progress on Theoretical Chemistry and Physics, S. D. Schwartz, Ed. (Kluwer Academic Publishers, Dordrecht, 2000), pp. 269–300. 6 www.quantumwise.com; Atomistix ToolKit version 10.8, QuantumWise A/S; (a) M. Brandbyge, J.-L. Mozos, P. Ordejón, J. Taylor, K. Stokbro, Density-functional method for nonequilibrium electron transport, Phys. Rev. B 65, 165401 (2002); (b) J. M. Soler, E. Artacho, J. D. Gale, A. García, J. Junquera, P. Ordejón, D. Sánchez-Portal, The SIESTA method for ab initio order-N materials simulation, J. Phys. Condens. Matter. 14, 2745–2779 (2002). 7 (a) J. P. Perdew, J. A. Chevary, S. H. Vosko, K. A. Jackson, M. R. Pederson, D. J. Singh, C. Fiolhais, Atoms, molecules, solids, and surfaces: Applications of the generalized gradient approximation for exchange and correlation, Phys. Rev. B 46, 6671–6687 (1992); (b) A. D. Becke, Density-functional exchange-energy approximation with correct asymptotic behavior, Phys. Rev. A 38, 3098–3100 (1988); (c) D. C. Langreth, M. J. Mehl, Beyond the local-density approximation in calculations of ground-state electronic properties, Phys. Rev. B 28, 1809–1834 (1983). 8 (a) J. P. Perdew, K. Burke, M. Ernzerhof, Generalized Gradient Approximation Made Simple, Phys. Rev. Lett. 77, 3865–3868 (1996); (b) J. P. Perdew, K. Burke, M. Ernzerhof, Generalized Gradient Approximation Made Simple [Phys. Rev. Lett. 77, 3865 (1996)], Phys. Rev. Lett. 78, 1396–1396 (1997). 9 DZP basis set. 10 A. Tkatchenko, M. Scheffler, Accurate Molecular Van Der Waals Interactions from Ground-State Electron Density and Free-Atom Reference Data, Phys. Rev. Lett. 102, 073005 (2011). 11 V. Blum, R. Gehrke, F. Hanke, P. Havu, V. Havu, X. Ren, K. Reuter, M. Scheffler, Ab initio molecular simulations with numeric atom-centered orbitals, Comput. Phys. Commun. 180, 2175-2196 (2009).

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respectively. To facilitate the direct comparison between two methods, we used the same computational criteria and parameters. The comparison between two methods, summarized in Supplementary Figs. 10-12 and Supplementary Table 7, shows only minor changes in the optimized structure and energies, which do not affect the main conclusions made in the manuscript. The theoretical nc-AFM images of the optimized adsorbates were calculated using the AFM simulator.12

12 P. Hapala et al., Phys. Rev. B 90, 085421 (2014).

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Supplementary Figure 1 | The enantiopure benzo[2,1-g:3,4-g']dichrysene (P)-DBH on Ag(111). (a) The STM overview image taken at 1.2 K, It = 20 pA, U = 500 mV, a molecular concentration: ~11.4 0.4 molecules per 10 x 10 nm2, size 80 × 80 nm2. (b) The zoom of 14 × 14 nm2 (the yellow square in a) shows the major trimers in the shape of the equilateral triangles (marked by the yellow circle (A)) along with the examples of the minor clusters: The triangular trimer rotated by 90o (B), bent trimer (C), and dimer (D). Every bright protrusion corresponds to a single molecule.

The statistics on the 727 molecules of (P)-DBH (Supplementary Figure 1a): Clusters Molecules % (Molecules) Major triangular trimers of (P)-DBH (A) 217 651 89.5 Minor triangular trimers of (P)-DBH (rotated by 60o) (B)

13 39 5.4

Bent trimers of (P)-DBH (C) 3 9 1.2 Dimers of (P)-DBH (D) 14 28 3.9 Monomeric (P)-DBH 0 0 0

(P)-DBH

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Supplementary Figure 2 | The racemic benzo[2,1-g:3,4-g']dichrysene (rac-DBH) on Ag(111). (a) The STM overview image taken at 1.2 K, It = 20 pA, U = 500 mV, a molecular concentration: ~11.1 + 0.4 molecules per 10 x 10 nm2, size 80 × 80 nm2. (b) The zoom of 14 x 14 nm2 shows mainly the observed dimers rotated by 60o (marked by a yellow circle (A)) and occasionally observed bent trimer (B). Every bright protrusion corresponds to a single molecule.

The statistics on the 708 molecules of rac-DBH (Supplementary Figure 2a): Clusters Molecules % (Molecules) Dimers of rac-DBH (A) 349 698 98.6 Bent trimers of rac-DBH (B) 3 9 1.3 Monomeric rac-DBH 1 1 0.1

rac-DBH

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Supplementary Figure 3 | The transformed enantiopure benzo[2,1-g:3,4-g']dichrysene (P)-DBH on Ag(111) by annealing at 520 K. (a), (b) The STM overview images taken at 1.2 K, It = 20 pA, U = 500 mV, a molecular concentration: ~8.6 0.4 molecules per 10 x 10 nm2, size 80 × 80 nm2. (c) The four-arm star tetramer of the nonplanar P1, size 4.4 × 4.4 nm2. (d) The dimer of the nonplanar P1, size 4 ×

4 nm2. (e) The trimer of the nonplanar P1, size 4 × 4 nm2. (f) The non-symmetrical flat P2, size 2 × 2 nm2. (g) The symmetrical flat P3, size 2 × 2 nm2. (h) Other flat adsorbates of an unknown structure (an example), size 2.3 × 2.3 nm2. The nonplanar molecular adsorbate P1 was seen in the STM images as a bright triangular protrusion coupled with an adjacent small bulge, the flat P2 and P3 appeared as single bright protrusions of the characteristic shapes.

The statistics on the 1 094 molecules (Supplementary Figures 3a and 3b): Clusters Molecules % (of all

molecules) Monomeric (P)-DBH or its clusters 0 0 0 Four-arm star tetramers of P1 64 256 23.4 Trimers of P1 7 21 1.9 Dimers of P1 304 608 55.5 Monomeric non-symmetrical P2 (flat) 0 140 12.8 Monomeric symmetrical P3 (flat) 0 49 4.5 Monomeric adsorbates of unknown structure (flat) 0 20 1.8

P1 P2 P3(P)-DBH

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Supplementary Figure 4 | The transformed enantiopure benzo[2,1-g:3,4-g']dichrysene (P)-DBH on Ag(111) by annealing at 520 K with the higher molecular coverage compared to Supplementary Figure 3. (a), (b) The STM overview images taken at 1.2 K, It = 20 pA, U = 500 mV, a molecular concentration: ~14.5 0.5 molecules per 10 x 10 nm2, size 80 × 80 nm2. (c) The four-arm star tetramer of the nonplanar P1, size 4.4 × 4.4 nm2. (d) The dimer of the nonplanar P1, size 4 × 4 nm2. (e) The trimer of the nonplanar P1, size 4 × 4 nm2. (f) The non-symmetrical flat P2, size 2 × 2 nm2. (g) The symmetrical flat P3, size 2 × 2 nm2. (h) Other flat adsorbates of an unknown structure (an example), size 2.3 × 2.3 nm2. The nonplanar molecular adsorbate P1 was seen in the STM images as a bright triangular protrusion coupled with an adjacent small bulge, the flat P2 and P3 appeared as single bright protrusions of the characteristic shapes.


molecules) Monomeric (P)-DBH or its clusters 0 0 0 Four-arm star tetramers of P1 230 920 49.6 Trimers of P1 12 36 1.9 Dimers of P1 285 570 30.7 Monomeric non-symmetrical P2 (flat) 0 235 12.7 Monomeric symmetrical P3 (flat) 0 76 4.1 Monomeric adsorbates of unknown structure (flat) 0 18 1.0

P1 P2 P3(P)-DBH

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Supplementary Figure 5 | The transformed enantiopure benzo[2,1-g:3,4-g']dichrysene (P)-DBH on Ag(111) by annealing at 670 K. (a), (b) The STM overview images taken at 1.2 K, It = 20 pA, U = 500 mV, a molecular concentration: ~8.3 0.4 molecules per 10 x 10 nm2, size 80 × 80 nm2. (c) The dimer of the nonplanar P1, size 4 × 4 nm2. (d) The non-symmetrical flat P2, size 2 × 2 nm2. (e) The symmetrical flat P3, size 2 × 2 nm2. (f) Other flat adsorbates of an unknown structure (an example), size 2.3 × 2.3 nm2. The nonplanar molecular adsorbate P1 was seen in the STM images as a bright triangular protrusion coupled with an adjacent small bulge, the flat P2 and P3 appeared as single bright protrusions of the characteristic shapes.


molecules) Monomeric (P)-DBH or its clusters 0 0 0 Four-arm star tetramers of P1 0 0 0 Trimers of P1 0 0 0 Dimers of P1 44 88 7.8 Monomeric non-symmetrical P2 (flat) 0 939 83.6 Monomeric symmetrical P3 (flat) 0 84 7.5 Monomeric adsorbates of unknown structure (flat) 0 12 1.1

P1 P2 P3(P)-DBH

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Supplementary Figure 6 | The STM-tip manipulation with the components of the four-arm star tetramers on Ag(111). The constant height STM images at 1.2 K, U = 50 mV, size 9 × 9 nm2. (a) The STM image of the tetramers consisting of the four molecules P1 taken before the manipulation; the yellow arrow points to the arm of the tetramer to be moved. (b) The same area imaged after the STM-tip manipulation; the yellow arrow points to the arm of the tetramer that was moved. The manipulation was performed by positioning the tip near the molecule in the direction of the manipulation and decreasing tip-sample distance until the molecule is pulled out.

P1

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Supplementary Figure 7 | The comparison of the experimental and calculated nc-AFM images of the non-covalent clusters of P1 and monomeric P2 and P3. The nc-AFM images were recorded with the Xe-functionalized tip at 1.2 K, the theoretical nc-AFM images were calculated using the AFM simulator.12 The experimental versus calculated nc-AFM images of the four-arm star tetramer of P1, size 4.4 × 4.4 nm2 (a vs. e), hourglass-shaped dimer of P1, size 3 × 3 nm2 (b vs. f), monomeric P2, size 2 × 2 nm2 (c vs. g) and monomeric P3, size 2 × 2 nm2 (d vs. h).

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Supplementary Figure 8 | The proposed mechanism of the cascade transformations of (P)-DBH to the coronene derivatives P1, P2, and P3 upon annealing on Ag(111) at 520 and 670 K. (a) The multiple bonds in (P)-DBH marked in green represent the diene and dienophile systems involved in the following Diels-Alder cycloaddition. The single bond in the intermediate B marked in green breaks on the way to the product P1. (b)-(e) The calculated trajectory of the initial Diels-Alder cycloaddition of (P)-DBH on Ag(111) to provide the intermediate A using the periodic DFT (GGA/PBE/DZP) and NEB algorithm to localize the transition state TS.

A note: An incomplete chirality transfer from the enantiopure (P)-DBH to the enantiofacially adsorbed P1 and P2 at 520 K is not a result of a partial racemization of these chiral adsorbates at this temperature. Instead, it can be ascribed to two different mechanisms. Either to a partial Ag(111)-catalyzed racemization of (P)-DBH (probably assisted by neighboring adsorbates) prior to its cascade transformations or to the competition between the two stereochemically distinct pathways of the initial [4+2] Diels-Alder cycloaddition (as a result of adsorption to Ag(111), (P)-DBH loses its C2 symmetry and, therefore, two distinguishable diene-dienophile systems may operate in the intramolecular cycloaddition reaction). It is worth noting that during the cascade transformation of

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the enantiopure (P)-DBH to the enantioenriched chiral adsorbates P1 and P2 no chiral-memory effect13 is involved as all intermediates (molecules or adsorbates) are chiral. Nevertheless, the incomplete chirality transfer from the enantiopure (P)-DBH to the enantiofacially adsorbed P1 and P2 and the mechanism of the on-surface racemization of (P)-DBH requires a further study.

13 (a) D. Seebach, D. Wasmuth, Alkylation of Amino Acids without Loss of Optical Activity: α- and β-Alkylation

of an Aspartic Acid Derivative. Angew. Chem. Int. Ed. 20, 971–971 (1981); (b) E. Yashima, K. Maeda, Y. Okamoto, Memory of macromolecular helicity assisted by interaction with achiral small molecules. Nature 399, 449–451 (1999).

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Supplementary Figure 9 | Assigning the handedness to the molecular adsorbates P1 and P2 formed after annealing the racemic rac-DBH on Ag(111) at 620 K for 5 min. (a) The constant height STM image taken at 1.2 K, U = 5 mV, a Xe-functionalized tip, a molecular concentration: ~27.2 3.9 molecules per 10 × 10 nm2, size 13 × 13 nm2. The image comprises the four-arm star tetramers composed of the four homochiral adsorbates P1, monomeric adsorbates P2, single hourglass-shaped dimer composed of the two homochiral adsorbates P1 and corrupted molecular cluster composed of the four adsorbates P1 of the mismatched handedness. The adsorbed Xe adatom is marked by an arrow. (b) The respective handedness of the adsorbates P1 forming the clusters is marked by the white contours. It is worth noting that the handedness of the individual adsorbates P1 in the clusters is defined by the position of the bright bulge (a phenyl substituent) with respect to the roughly right-angle corner of the corresponding triangle (a dibenzo[a,g]coronene core unit). (c) The beige and cyan spots represent the molecular adsorbates P1 (in the clusters) and P2 (monomers) sorted by their handedness; red spots represent the achiral molecular adsorbates P3 (monomers).

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Supplementary Figure 10 | Comparison of optimized geometries of the (P)-DBH and intermediate A in vacuo using QW/cc-pVDZ/b3lyp+vdW-b97d and FHI-AIM/b3lyp+vdW-TS calculations schemes. (a) Optimized atomic structure of (P)-DBH. (b) Optimized atomic structure of intermediate A. Both calculation schemes provide very similar atomic structures of the molecule.

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Supplementary Figure 11 | Comparison of optimized geometries of the (P)-DBH and intermediate A on the Ag(111) surface using QW/cc-pVDZ/PBE+vdW-b97d and FHI-AIM/PBE+vdW-TS calculation methods. (a) Optimized atomic structure of (P)-DBH. (b) Optimized atomic structure of intermediate A. Both methods optimize (P)-DBH in nearly the same way, however, an angle (α) between opposite

carbon rings of the intermediate A is larger from FHI-AIM/PBE+vdW-TS method.

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Supplementary Figure 12 | Comparison of optimized geometries of the dimer P1 on the Ag(111) surface using different calculations schemes. (a) The atomic structure optimized by cc-pVDZ/PBE+vdW-b97d. (b) The atomic structure optimized by FHI-AIMS/PBE+vdW-TS. The FHI-AIMS/PBE+vdW-TS scheme results in a smaller inter-molecule distance d, larger angle between the planes of phenyl rings α, and slightly larger dimer-surface separation h.

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Entry Molecular adsorbate

Clusters/ monomers

Number of molecules

Handedness 1

Handedness 2

Enantiomer ratio (%)

1 P1 tetramers 256 256 0 92:8 (all P1) 2 trimers 21 21 0 3 dimers 608 536 72 4 P2 monomers 140 127 13 91:9 5 P3 monomers 49 achiral 6 unidentified monomers 20 nd nd

Supplementary Table 1 | The statistics of the molecular adsorbates P1, P2, and P3 and their possible handedness after annealing (P)-DBH on Ag(111) at 520 K for 5 min. The STM overview images taken at 1.2 K, It = 20 pA, U = 500 mV, a molecular concentration: ~8.6 0.4 molecules per 10 x 10 nm2, size 80 × 80 nm2. The statistics is based on the analysis of the STM images a+b (in total 1 094 molecules). The enantiomer ratio corresponds to the ratio between the adsorbates exhibiting the handedness 1 or 2; the arbitral assignment of the handedness 1 and 2 to the molecular adsorbates P1 and P2 is expressed in Fig. 4 and Supplementary Fig. 9.

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Clusters/ monomers

Number of molecules

Handedness 1

Handedness 2



Supplementary Table 2 | The statistics of the molecular adsorbates P1, P2, and P3 and their possible handedness after annealing (P)-DBH on Ag(111) at 555 K for 5 min. The STM overview images taken at 1.2 K, It = 20 pA, U = 500 mV, a molecular concentration: ~7.9 0.4 molecules per 10 x 10 nm2, size 80 × 80 nm2. The statistics is based on the analysis of the STM image a+b (in total 988 molecules). The enantiomer ratio corresponds to the ratio between the adsorbates exhibiting the handedness 1 or 2; the arbitral assignment of the handedness 1 and 2 to the molecular adsorbates P1 and P2 is expressed in Fig. 4 and Supplementary Fig. 9.

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Clusters/ monomers

Number of molecules

Handedness 1

Handedness 2



Supplementary Table 3 | The statistics of the molecular adsorbates P1, P2, and P3 and their possible handedness after annealing (P)-DBH on Ag(111) at 590 K for 5 min. The STM overview images taken at 1.2 K, It = 20 pA, U = 500 mV, a molecular concentration: ~8.0 0.4 molecules per 10 x 10 nm2, size 80 × 80 nm2. The statistics is based on the analysis of the STM image a+b (in total 1 019 molecules). The enantiomer ratio corresponds to the ratio between the adsorbates exhibiting the handedness 1 or 2; the arbitral assignment of the handedness 1 and 2 to the molecular adsorbates P1 and P2 is expressed in Fig. 4 and Supplementary Fig. 9.

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Clusters/ monomers

Number of molecules

Handedness 1

Handedness 2



Supplementary Table 4 | The statistics of the molecular adsorbates P1, P2, and P3 and their possible handedness after annealing (P)-DBH on Ag(111) at 625 K for 5 min. The STM overview images taken at 1.2 K, It = 20 pA, U = 500 mV, a molecular concentration: ~8.2 0.4 molecules per 10 x 10 nm2, size 80 × 80 nm2. The statistics is based on the analysis of the STM image a+b (in total 1 052 molecules). The enantiomer ratio corresponds to the ratio between the adsorbates exhibiting the handedness 1 or 2; the arbitral assignment of the handedness 1 and 2 to the molecular adsorbates P1 and P2 is expressed in Fig. 4 and Supplementary Fig. 9.

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Clusters/ monomers

Number of molecules

Handedness 1

Handedness 2


1 P1 tetramers 0 49:51 (all P1) 2 trimers 0 3 dimers 88 43 45 4 P2 monomers 939 471 468 50:50 5 P3 monomers 84 achiral 6 unidentified monomers 12 nd nd

Supplementary Table 5 | The statistics of the molecular adsorbates P1, P2, and P3 and their possible handedness after annealing (P)-DBH on Ag(111) at 670 K for 5 min. The STM overview images taken at 5 K, It = 20 pA, U = 500 mV, a molecular concentration: ~8.8 0.4 molecules per 10 x 10 nm2, size 80 × 80 nm2. The statistics is based on the analysis of the STM image a+b (in total 1 123 molecules). The enantiomer ratio corresponds to the ratio between the adsorbates exhibiting the handedness 1 or 2; the arbitral assignment of the handedness 1 and 2 to the molecular adsorbates P1 and P2 is expressed in Fig. 4 and Supplementary Fig. 9.

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Clusters/ monomers

Number of molecules

Handedness 1

Handedness 2


1 P1 tetramers 76 0 76 18:82 (all P1) 2 trimers 6 3 3 3 dimers 318 68 250 4 P2 monomers 15 2 13 13:87 5 P3 monomers 10 achiral 6 unidentified monomers - - -

Supplementary Table 6 | The statistics of the molecular adsorbates P1, P2, and P3 and their possible handedness after annealing the enantioenriched (M)-DBH (M: 933%, P: 73%) on Ag(111) at 520 K for 5 min. (a) The STM image before annealing. (b) The STM image after annealing. The STM overview images taken at 5 K, It = 20 pA, U = 500 mV, a molecular concentration: ~6.6 0.3 molecules per 10 x 10 nm2, size 80 × 80 nm2. The statistics is based on the analysis of the STM image a (in total 425 molecules). The enantiomer ratio corresponds to the ratio between the adsorbates exhibiting the handedness 1 or 2; the arbitral assignment of the handedness 1 and 2 to the molecular adsorbates P1 and P2 is expressed in Fig. 4 and Supplementary Fig. 9.

The lower optical purity of the enantioenriched (M)-DBH (93:7 M:P enantiomer ratio) resulted from an incomplete separation of enantiomers by high performance liquid chromatography on a column with chiral stationary phase (even after repeated separations). Annealing the enantioenriched (M)-DBH on Ag(111) at 520 K for 5 min (similarly as it was done with (P)-DBH, Supplementary Table 1), we performed the statistics of the major molecular adsorbate P1 and its handedness (inspecting in total 425 molecules). Accordingly, (M)-DBH provided 400 molecules P1 of the prevailing handedness 2 (handedness 1:handedness 2=18:82) representing thus a "mirror image" of the experiment with (P)-DBH (handedness 1:handedness 2=92:8). The formally diminished chirality transfer in the transformation of (M)-DBH can be explained by its lower optical purity: Provided the chirality transfer proceeds with the 92% efficiency (Supplementary Table 1), a 93:7 mixture of (M)- and (P)-DBH should lead to a 86:14 mixture of chiral adsorbates formed by P1. The experimental observation (82:18) corresponds to that (within a 5% experimental error).

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Method Es ETS E Surface separation (Å) (kcal/mol) (kcal/mol) (kcal/mol) DBH Intermediate A

cc-pVDZ/b3lyp + vdW-b97d -80.71 26.45 3.91 ̴3.2 ̴3.1 FHI-AIM/b3lyp + vdW-TS -115.4 24.15 1.15 ̴3.2 ̴3.1

Supplementary Table 7 | Comparison of the calculated relevant energies and surface separation of (P)-DBH and the intermediate A of the initial Diels-Alder cycloaddition on Ag(111) using cc-pVDZ/PBE+vdW-b97d and FHI-AIM/b3lyp+vdW-TS calculation methods. Es – adsorption energy of (P)-DBH; ETS – activation energy of the reaction (P)-DBH → intermediate A; E – energy difference between (P)-DBH and the intermediate A (see Supplementary Fig. 11); surface separation – a distance between the molecular plane (the closest-to-surface parallel aromatic rings) and the Ag(111) surface (see Supplementary Fig. 11).

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