THE IINS SPECTROSCOPY OF AMINO-ACIDS - L-ISOLEUCINE

Results of inelastic incoherent neutron scattering (IINS) supplemented by infrared (IR) and Raman scattering studies on normal and N-deutera ted L-isoleucine in the energy transfer up to 800 cm(-1) are reported. The IINS spectra of L-isoleucine show additional bands as compared to the spectra obtained by optical spectroscopic methods. In both, norma l and d(3)-L-isoleucine, extra bands correspond to out-of-plane gamma( N-H ... O) (518, 505, 250 cm(-1)) and gamma(N-DO ... O) (362 cm(-1)) h ydrogen bond vibrations. Methyl and carboxyl groups vibrations are obs erved at 219, 228, 250, 281 cm(-1) and 175, 543, 686, 749 cm(-1) respe ctively. (C) 1997 Elsevier Science B.V.