Firing salts method for the synthesis of orthorhombic Gd₂TiO₅: experimental characterization supported by DFT first principles calculations

This work presents the synthesis by the new ‘firing salts method’ (FSM) of orthorhombic Gd ₂ TiO ₅ which requires only two hours at 1200 °C. X Ray Diffraction, High Resolution Transmission Electron Microscopy, Fourier Transform Infrared Spectroscopy and Raman spectroscopy characterized it. Electron microscopy shows particle size distribution between 50–500 nm with orthorhombic structure according to Rietveld analysis. Raman—infrared spectroscopies and first principles calculations indicate that the second order contribution to the spectra comes from the Ti-O5 interactions. First principles calculations (Density Functional Theory) were used as an aid for the interpretation of the experimental results to assign the normal modes to the bands on the Raman and IR spectra; it also provided an insight of the chemical reactivity of the synthesis.