Solid Phase Relationships in Systems of Amino Acid Enantiomers in Connection with Their Participation in Geological and Technological Processes

The present article sets forth the results of experimental investigations of solid phase interactions in chiral systems of the following types: (1) systems composed of enantiomers of one amino acid, the representative examples being L-threonine—D-threonine and L-phenylglycine—D-phenylglycine; (2) systems composed of diastereomers of one amino acid, the representative examples being L-threonine—L-allo-threonine and D-threonine—L-allo-threonine; and (3) systems composed of left enantiomers of different amino acids exemplified by the following pairs: L-valine—L-isoleucine, L-valine—L-leucine, L-leucine—L-isoleucine, L-alanine—L-serine, and L-aspartic acid—L-glutamic acid. The limits of solid solutions in the above systems are analyzed and possibility of formation of equimolar and non-equimolar discrete compounds is considered. Thermal deformations of crystal structures of the components involved, as well as thermal deformations of several solid solutions formed are investigated and the figures of thermal expansion coefficients (CTE) are plotted. Systematization of organic compounds formed in the binary chiral systems is proposed. The availability of the investigation is closely connected to an important part the amino acids play in both natural processes and technological applications.