RESUMEN
The aggregation of (pro)chiral/achiral molecules into crystalline structures at interfaces forms conglomerates, racemates, and solid solutions, comparable to known bulk phases. Scanning tunneling microscopy and Monte Carlo simulations were employed to uncover a distinct racemic phase, expressing 1D disordered chiral sorting through random tiling in surface-confined supramolecularly assembled achiral 4,4''-diethynyl-1,1':4',1''-terphenyl molecules. The configurational entropy of the 1D disordered racemic tiling phase was verified by analytical modeling, and found to lie between that of a perfectly ordered 2D racemate and a racemic solid solution.
RESUMEN
Two-dimensional tiling manners as cross-sectional views of cylindrical domain assembly formed by pentablock quarterpolymers of the AB1CB2D type in bulk were investigated. Several binary and ternary blends from three mother polymers having different ÏB1/ÏB2 ratios (ÏB1 and ÏB2 are the volume fractions of the B1 and B2 blocks, respectively) represent nonperiodic but ordered triangle/square tilings, where the N3/N4 ratios (N3 and N4 are the numbers of triangles and squares in the observed area, respectively) are all close enough to the theoretical value of 4/â3 â 2.31 for the dodecagonal quasicrystalline (DDQC) state, irrespective of the total number of polygons. The TEM images, having almost the same N3/N4 ratios, were proved to show 4- and 6-fold symmetries in terms of the angular appearance of equilateral polygon sides via image analyses. Among them, a ternary blend showed a nearly ideal random tiling pattern that is almost equivalent to the theoretically predicted tiling by SCFT. Moreover, the magnitude of phason strain estimated for a TEM image from the ternary blend was proved to be quite small when the observing area is narrow, while it deviates from the ideal quasicrystalline tiling with an increasing number of vertices in the observing area.