Pressure-dependence Raman spectroscopy and the lattice dynamic calculations of Bi2(MoO4)3 crystal.

[Display omitted] • Vibrational properties of the Bi 2 (MoO 4) 3 at room temperature. • Lattice dynamic calculations based on the rigid ion model. • Effect of the pressure on the vibrational properties of the Bi 2 (MoO 4) 3. • Pressure-induced phase transformation in the Bi 2 (MoO 4) 3. This work reports a pressure-dependent Raman spectroscopic study and the theoretical lattice dynamics calculations of a Bi 2 (MoO 4) 3 crystal. The lattice dynamics calculations were performed, based on a rigid ion model, to understand the vibrational properties of the Bi 2 (MoO 4) 3 system and to assign the experimental Raman modes under ambient conditions. The calculated vibrational properties were helpful to support pressure-dependent Raman results, including eventual structural changes induced by pressure changes. Raman spectra were measured in the spectral region between 20 and 1000 cm−1 and the evolution of the pressures values was recorded in the range of 0.1–14.7 GPa. Pressure-dependent Raman spectra showed changes observed at 2.6, 4.9 and 9.2 GPa, these changes being associated with structural phase transformations. Finally, principal component analysis (PCA) and hierarchical cluster analysis (HCA) were performed to infer the critical pressure of phase transformations undergone by the Bi 2 (MoO 4) 3 crystal. [ABSTRACT FROM AUTHOR]