| Abstract
| - The effect of the chirality on the thermodynamic behavior, the morphological features, and the 2D crystalstructures of 1-stearylamine-glycerol monolayers are studied. The results are based on measurements of thesurface pressure−area (π−A) isotherms, fluorescence microscopy, and synchrotron X-ray diffraction at grazingincidence (GIXD). Although the π−A isotherms of the enantiomeric forms and the racemic mixtures agreelargely to each other, the filigree domain patterns show remarkable differences, obviously driven by thechirality. The domains of the R(+) enantiomer are curved clockwise, those of the S(−) enantiomercounterclockwise, whereas those of the racemic mixtures are without a specific sense of direction. Chiraldiscrimination effects are also found in the lattice structure. The enantiomeric monolayers have an obliquelattice where at compression the tilt direction changes continuously from angles nearly toward NN directionto angles nearly toward NNN direction. The condensed phases of the 1:1 racemic mixtures give rise torectangular-centered lattices indicating a phase transition accompanied by the change in the tilt directionfrom NN at 1 mN/m to NNN at 5 mN/m. The filigree domain patterns indicate a comparatively low orderingof the alkyl chains. Correspondingly, a short-range translational order can be concluded from the low positioncorrelation and high tilt angles of the alkyl chains at low surface pressures.
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