Chirality in chemistry concerns to the study of compounds, which molecular structure shows enantiomeric forms, i. e. the property that the mirror image of the molecular structure cannot be brought to coincide with itself (Lord Kelvin, Baltimore Lectures, 1884). This mirror symmetry breaking may be also be shown by classical objects, therefore the question is in which degree classical objects may shown a chemical behavior that we relate with chemical chirality. A more modern definition says that “chirality is shown by systems existing in two distinct enantiomeric states that are interconvert by space inversion, but not by time reversal combined with any proper spatial rotation” (L. Barron, 1980). This last definition also includes motion and therefore is more related to the physical description of chirality, however, after the recognition of the CP violation, the paradox arises that chemical enantiomers are not true enantiomers. This surprisingly agree with the old statement made in the discovery of chemical chirality that chemical chirality is the consequence of a chiral Universe (Pasteur,1848). The chemical meaning of chirality is in fact defined in the interaction of enantiomers with a chiral property or with other chiral compound (yielding different free energy changes), which also applies to the interaction between enantiomers. Therefore, when enantiomers are not observed by a chiral property they are thermodynamic identical entities. Chemistry begins in the consideration of atoms and molecules as classical objects, i.e. in the emergence of a new property, the molecular structure, by the formation of atoms and molecules. Here the mirror symmetry breaking yielding enantiomers is also a emergent new property. In the upper level of chemical complexity there is Life, where complexity determines the emergence of new properties of self-replication and Darwinian evolution. In this high border of Chemistry, the emergence of Life. A short description of the activity of the research group in spontaneous mirror symmetry breaking in Chemistry will be given.

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THIS SEMINAR WILL BE IN CATALAN