First-Principles Calculation of MoO₂ and MoO₃ Electronic and Optical Properties Compared with Experimental Data

Area of Science:

• Materials Science
• Condensed Matter Physics
• Computational Chemistry

Background:

• Molybdenum trioxide (MoO3) and molybdenum dioxide (MoO2) exhibit unique electronic and optical properties, driving interest in their applications.
• MoO3 crystallizes in a stable orthorhombic phase (α-MoO3, space group Pbmn), while MoO2 adopts a monoclinic structure (space group P21/c).
• Understanding the nature of Mo-O bonds is crucial for predicting and optimizing the properties of these materials.

Purpose of the Study:

• To investigate the electronic and optical properties of MoO3 and MoO2 using advanced computational methods.
• To employ the Meta Generalized Gradient Approximation (MGGA) SCAN functional and PseudoDojo pseudopotential for accurate material property prediction.
• To gain deeper insights into the diverse Mo-O bonding characteristics within these molybdenum oxide systems.

Main Methods:

• Density Functional Theory (DFT) calculations were performed.
• The SCAN (MGGA) functional combined with PseudoDojo pseudopotentials was utilized for the first time for these systems.
• Calculated electronic properties (density of states, band gap, band structure) and optical spectra were validated against experimental data.

Main Results:

• The calculated electronic and optical properties of MoO3 and MoO2 showed excellent agreement with existing experimental results.
• The band gap energy of orthorhombic MoO3 closely matched experimentally reported values.
• The study successfully validated the accuracy of the employed theoretical techniques in reproducing experimental evidence.

Conclusions:

• The combination of SCAN (MGGA) functional and PseudoDojo pseudopotentials provides a highly accurate theoretical approach for studying molybdenum oxides.
• These computational findings confirm the reliability of DFT for predicting the electronic and optical behavior of MoO2 and MoO3.
• The validated methods offer a powerful tool for future research and development involving these important materials.