Spontaneous Chiral Segregation in Bidimensional Films

We have monitored spontaneous chiral segregation in Langmuir films of a racemic mixture of $D$ and $L$ myristoyl-alanine. Following monolayer deposition, we observe first a strong chiral discrimination, followed at longer times by a spatial segregation between $D$ and $L$ domains. Evidence for discrimination has been obtained by surface pressure/area per molecule measurements, whereas segregation is inferred from optical observations using epifluorescence microscopy and from an analysis of the lattice symmetry using x-ray diffraction.