Phase behaviour of self-assembled monolayers controlled by tuning physisorbed and chemisorbed states: A lattice-model view

Abstract

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From a bistable adsorbate to a switchable interface: tetrachloropyrazine on Pt(111)

“…14 Here, we use temperature and pressure to switch adlayers of molecules that exhibit a doublewell potential when adsorbing on a substrate. Examples for systems with double-well potentials include benzene derivatives on Pt(111), [15][16][17] tetrafluoropyrazine on Ni(111) 18 and anthradithiophene on Cu(111). [19][20][21] Related examples are molecules adopting different conformers upon adsorption.…”

Exploring self‐organization of molecular tether molecules on a gold surface by global structure optimization

“…In light of these fundamental difficulties, additional limiting assumptions were frequently employed, for example, lattice models, enabling treatments of up to 1025 molecules. Of course, instead of discretizing space into a lattice model, it is also possible to achieve significant speed‐ups in a continuous‐space approach, by restricting the molecular models themselves, for example, employing coarse‐grained force‐fields, fully rigid molecules and linearly interpolated forces, or other highly simplified descriptions, again enabling treatments of up to 1200 molecules.…”

Influence of Molecule–Surface and Molecule–Molecule Interactions on Two-Dimensional Patterns Formed by Functionalized Aromatic Molecules

“…It has been shown that on platinum the relative stability of the chemisorbed and physisorbed states of benzene molecules can be tuned by adjusting the ring functionalisation [17][18][19][20] and, hence, that the molecule-surface interaction can be used to control the structure of the self-assembled monolayer. 21 The collective molecular behavior is affected by the interplay among different interactions and lattice models have been shown to capture experimentally observed patterns. For instance hexagonal and square lattice models 22 successfully described self-assembled molecular systems on surfaces.…”

“…For instance hexagonal and square lattice models 22 successfully described self-assembled molecular systems on surfaces. 21,[23][24][25][26][27] The effect of the strength of the molecule-surface interaction was recently taken into account in a three-dimensional model for the study of triangular molecules at the solid-liquid interface 28 and in two dimensional models for the study of molecules on platinum surfaces. 21 If the adsorbed molecules are rigid, flat molecules presenting hexagonal symmetry, e.g.…”

“…21 Only the weakly bound (physisorbed) state allowed for 3 free diffusion along the surface resulting in a ordered packed state. 21 Our model gave qualitative agreement to experiment and found that benzene monolayers were disordered and halogenation (chloro-and bromination) resulted in ordering, 21 which was qualitatively similar to experimental results that fluorination increased ordering of pentacene monolayers. 10 In this paper, we generalise our model to describe molecules with hexagonal symmetry (such as hexasubstituted benzene rings 20 and larger aromatic compounds).…”