[Structure and Raman spectra of titanium oxides]

Area of Science:

• Materials Science
• Computational Chemistry
• Solid-State Physics

Context:

• Titanium oxides exhibit diverse structures and properties relevant to catalysis, energy storage, and electronics.
• Accurate structural and vibrational characterization is crucial for understanding material behavior.
• Experimental techniques like X-ray diffraction and Raman spectroscopy provide valuable data but require theoretical support for interpretation.

Purpose:

• To optimize the crystal structures of various titanium oxides (TiO, Ti2O3, Ti3O5, anatase, and rutile) using first-principle density functional theory.
• To calculate and assign molecular vibrational modes for these titanium oxides.
• To interpret experimental Raman spectra by comparing them with calculated vibrational wavenumbers, enabling the identification of different titanium oxide types.

Summary:

• First-principle density functional theory calculations were employed to optimize the structures of TiO, Ti2O3, Ti3O5, anatase, and rutile.
• The optimized structural parameters showed excellent agreement with experimental X-ray diffraction results.
• Calculated vibrational wavenumbers, obtained using a double numeric with D-polarization function basis set and local density approximation, were used to interpret experimental Raman spectra.
• Characteristic peaks in the Raman spectra were assigned to specific titanium oxide types, facilitating their diagnosis and recognition.

Impact:

• Provides a reliable theoretical method for identifying and distinguishing between different titanium oxide phases.
• Facilitates the investigation of structure-property correlations in titanium oxide materials.
• Enhances the understanding of titanium oxide behavior in various applications, potentially guiding material design and selection.