Supporting data for the paper 'State Space Reduction and Equivalence Class Sampling for a Molecular Self-Assembly Model'

The equivalence class sample used to generate Figure 5 as an .Rdata workspace file for R. Upon loading this data into the R environment, one should type “Message” to receive an explanation of the data structure

Co-Location of Air Capture, Subseafloor CO₂ Sequestration, and Energy Production on the Kerguelen Plateau

Reducing atmospheric CO₂ using a combination of air capture and offshore geological storage can address technical and policy concerns with climate mitigation. Because CO₂ mixes rapidly in the atmosphere, air capture could operate anywhere and in principle reduce CO₂ to preindustrial levels. We investigate the Kerguelen plateau in the Indian Ocean, which offers steady wind resources, vast subseafloor storage capacities, and minimal risk of economic damages or human inconvenience and harm. The efficiency of humidity swing driven air capture under humid and windy conditions is tested in the laboratory. Powered by wind, we estimate ∼75 Mt CO₂/yr could be collected using air capture and sequestered below seafloor or partially used for synfuel. Our analysis suggests that Kerguelen offers a remote and environmentally secure location for CO₂ sequestration using renewable energy. Regional reservoirs could hold over 1500 Gt CO₂, sequestering a large fraction of 21st century emissions

Adsorbate-Promoted Tunneling-Electron-Induced Local Faceting of D/Pd{110}-(1 × 2)

We have utilized tunneling electrons and thiophene adsorption to draw deuterium (D) from within the single-crystal bulk beneath Pd{110} up to subsurface adsorption sites. We found local faceting induced by this process, and determined the energy threshold of drawing bulk D to subsurface sites to be 0.38 ± 0.02 eV. We show that these facets propagate along the ⟨11̅0⟩ direction of the substrate, and that Pd{110} adopts the (1 × 1) surface reconstruction on the induced facets, yet maintains the paired row (1 × 2) structure on unaffected regions. After producing subsurface D, the facet plane tilts 3.2 ± 0.8° off the substrate plane

Adsorbate-Promoted Tunneling-Electron-Induced Local Faceting of D/Pd{110}-(1 × 2)

We have utilized tunneling electrons and thiophene adsorption to draw deuterium (D) from within the single-crystal bulk beneath Pd{110} up to subsurface adsorption sites. We found local faceting induced by this process, and determined the energy threshold of drawing bulk D to subsurface sites to be 0.38 ± 0.02 eV. We show that these facets propagate along the ⟨11̅0⟩ direction of the substrate, and that Pd{110} adopts the (1 × 1) surface reconstruction on the induced facets, yet maintains the paired row (1 × 2) structure on unaffected regions. After producing subsurface D, the facet plane tilts 3.2 ± 0.8° off the substrate plane

Self-Assembly Strategy for Fabricating Connected Graphene Nanoribbons

We use self-assembly to fabricate and to connect precise graphene nanoribbons end to end. Combining scanning tunneling microscopy, Raman spectroscopy, and density functional theory, we characterize the chemical and electronic aspects of the interconnections between ribbons. We demonstrate how the substrate effects of our self-assembly can be exploited to fabricate graphene structures connected to desired electrodes

Bottom-Up Graphene-Nanoribbon Fabrication Reveals Chiral Edges and Enantioselectivity

We produce precise chiral-edge graphene nanoribbons on Cu{111} using self-assembly and surface-directed chemical reactions. We show that, using specific properties of the substrate, we can change the edge conformation of the nanoribbons, segregate their adsorption chiralities, and restrict their growth directions at low surface coverage. By elucidating the molecular-assembly mechanism, we demonstrate that our method constitutes an alternative bottom-up strategy toward synthesizing defect-free zigzag-edge graphene nanoribbons

Precursor Geometry Determines the Growth Mechanism in Graphene Nanoribbons

On-surface synthesis with molecular precursors has emerged as the de facto route to atomically well-defined graphene nanoribbons (GNRs) with controlled zigzag and armchair edges. On Au(111) and Ag(111) surfaces, the prototypical precursor 10,10′-dibromo-9,9′-bianthryl (DBBA) polymerizes through an Ullmann reaction to form straight GNRs with armchair edges. However, on Cu(111), irrespective of the bianthryl precursor (dibromo-, dichloro-, or halogen-free bianthryl), the Ullmann route is inactive, and instead, identical chiral GNRs are formed. Using atomically resolved noncontact atomic force microscopy (nc-AFM), we studied the growth mechanism in detail. In contrast to the nonplanar BA-derived precursors, planar dibromoperylene (DBP) molecules do form armchair GNRs by Ullmann coupling on Cu(111), as they do on Au(111). These results highlight the role of the substrate, precursor shape, and molecule–molecule interactions as decisive factors in determining the reaction pathway. Our findings establish a new design paradigm for molecular precursors and opens a route to the realization of previously unattainable covalently bonded nanostructures