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Hydrogen bonds in crystalline d-alanine: diffraction and spectroscopic evidence for differences between enantiomers.

ABSTRACT: Enantiomeric amino acids have specific physiological functions in complex biological systems. Systematic studies focusing on the solid-state properties of d-amino acids are, however, still limited. To shed light on this field, structural and spectroscopic studies of d-alanine using neutron powder diffraction, polarized Raman scattering and ab initio calculations of harmonic vibrational frequencies were carried out. Clear changes in the number of vibrational modes are observed as a function of temperature, which can be directly connected to variations of the N-D bond lengths. These results reveal dissimilarities in the structural properties of d-alanine compared with l-alanine.

SUBMITTER: Belo EA

PROVIDER: S-EPMC5755572 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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