Vibrational spectra of l-lysine monohydrochloride dihydrate and its two anhydrous forms

ATR FTIR and Raman spectra of l-Lys·HCl·2H2O and two crystalline forms of anhydrous l-Lys·HCl are reported and discussed. Distinction with earlier published IR spectra of l-Lys·HCl·2H2O registered by the KBr pellet method is explained by distortion of the spectra because of possible ionic exchange and partial decomposition.