Two-dimensional crystals from reduced symmetry analogues of trimesic acid.

The two-dimensional assembly of multicarboxylated arenes is explored at the liquid-graphite interface using scanning tunneling microscopy. Symmetry variations were introduced via phenylene spacer addition and the influence of these perturbations on the formation of hydrogen-bonded motifs from an alkanoic acid solvent is observed. This work demonstrates the importance of symmetry in 2D crystal formation and draws possible links of this behavior to prediction of coordination modes in three-dimensional coordination polymers.