High-pressure structural phase transition in $\mathrm{MnWO_{4}}$

The pressure-induced phase transition of the multiferroic manganese tungstate MnWO$_{4}$ is studied on single crystals using synchrotron x-ray diffraction and Raman spectroscopy. We observe the monoclinic P2/c to triclinic P1 phase transition at 20.1 GPa and get insight on the phase transition mechanism from the appearance of tilted triclinic domains. Selective Raman spectroscopy experiments with single crystals have shown that the onset of the phase transition occurs 5 GPa below the previously reported pressure obtained from experiments performedwith powder samples