VIBRATIONAL-SPECTRA AND INTER-MOLECULAR POTENTIAL OF DL-SERINE CRYSTAL

Polarized Raman spectra of dl-serine and O, N-deuterated dl-serine single crystals and i.r. spectra of their polycrystalline samples have been measured. A normal coordinate analysis has been made for the optical-active intra- and intermolecular vibrations. Large factor group splittings observed for the CO-2 antisymmetric stretching mode have been explained well by using a model potential function including the coupling terms due to the interaction between the transition dipoles induced by the vibration. This type of interaction has proved to explain well the variation in signs and magnitudes of the splittings of the antisymmetric and the symmetric CO-2 stretching modes of the simple amino acids, α-glycine, l-alanine and dl-alanine, in the crystalline state. © 1979.