Phonon modes of monoclinic BiB3O6
  We present a detailed study of the phonon modes of the monoclinic compound BiB3O6 based on polarized reflectivity measurements on single crystals. The spectra are analysed by means of a generalized Drude-Lorentz model, which allows us to resolve the modes of A and B symmetry. 
A. G\"ossling, T. M\"oller, W.-D. Stein, P. Becker, L. Bohat\'y, and   M. Gr\"uninger