Modified UBFF calculations of the alpha-L-fucopyranose molecule in the crystalline state.

Normal co-ordinate analysis has been realised in the crystalline state using a modified Urey-Bradley-Shimanouchi force field combined with an intermolecular potential energy function that includes van der Waals interactions, some electrostatic terms and an explicit hydrogen bond function. The vibrational spectra of the alpha-L-fucose molecule have been recorded in the crystalline state, in the 4000-500 cm(-1) spectral region for the mid-IR spectra, in the 500-100 cm(-1) spectral region for the far-IR spectra, and in the 4000-20 cm(-1) spectral range for Raman spectra. These spectra constitute the experimental support for the establishment of a force field for the molecule in the crystalline state through a normal co-ordinate analysis.