Raman spectroscopy (Figure 3) and XRD analysis (Figure 4) confirm that samples sintered at 900 °C and higher temperatures are crystalline ZrTiO4. ZrTiO4 with orthorhombic symmetry (space group Pbcn) and two formula units in a unit cell has 33 optically active modes of vibration, 18 of which are Raman active.
ZrTiO4 crystallizes with Pnab space group and α-PbO structure type, having two formula units in unit cell. Thus, ZrTiO4 has 33 optically active modes of vibration of which 18 are Raman active modes [16].