Vibrational properties of the nonlinear optical crystal β-BaTeMo2O9

We report growth of large single crystals of β-BaTeMo2O9, and single crystal infrared (IR) reflectance spectra as well as polarized Raman spectra for these crystals. Based on these results, the symmetry and LO–TO splitting have been established for the observed modes. We also propose assignment of the observed modes to the respective vibrations of structural units.

► β-BaTeMo2O9 single crystal was grown.
► Assignment has been proposed on basis of polarized IR and Raman spectra.
► Large LO–TO splitting was observed for some stretching and bending modes.