Temperature-Dependent Spectroscopy of Rutile Tin Dioxide*

The present spectroscopic investigation focuses on rutile tin dioxide (SnO₂) in powder form. Raman spectroscopy with laser excitation at 780 nm has been used to characterize the different vibrational modes of SnO₂. Thermal effects on the vibrational features in the Raman spectrum have been studied in the range 30 – 170 °C. We have demonstrated a red-shift in the Raman spectra as the temperature increases for both Α_1g (634 cm^-1) and B_2g (775 cm^-1), while E_g (475 cm^-1) exhibited little change. FT-IR spectra have been obtained in order to study the IR-active vibrational modes for tin dioxide: Sn-O stretching vibration at 467.36 cm^-1 and Sn-O-Sn asymmetric vibration at 569.37 cm^-1. X-ray diffraction (XRD) spectra have been recorded to confirm the rutile structure of tin dioxide. Scanning Electron Microscope (SEM) images have provided information regarding the size of the spherical grain particles. Molecular Dynamic simulation (MD) has been utilized to study the various vibrational modes at different temperatures using the LAMMPS software.