First-Principles Investigation of Structural, Electronic, X-ray Spectroscopic, and Optical Properties of CaRhH₃
DOI:
https://doi.org/10.54536/jir.v4i2.7586Keywords:
Artificial Intelligence, Carhh₃, Castep, Density Functional Theory, Electronic Structure, achine Learning, Metal Hydrides, Optical PropertiesAbstract
The CaRhH₃ compound has recently attracted attention due to its potential application in hydrogen energy systems; however, its electronic and optical properties remain insufficiently explored. In this work, density functional theory (DFT) calculations within the CASTEP framework are employed to systematically investigate the structural, electronic, and optical characteristics of CaRhH₃. Structural stability is confirmed through full geometry optimization and simulated powder X-ray diffraction analysis. The calculated electronic band structure indicates metallic behavior, primarily governed by Rh-d states near the Fermi level. To enhance the reliability of the electronic structure analysis, Gaussian Process Regression (GPR)-based machine learning is applied to the density of states (DOS), enabling smooth profile generation and uncertainty quantification. This approach significantly improves peak identification and interpretation of electronic features. Furthermore, element-specific X-ray absorption and emission spectrum provide detailed insight into the contributions of Ca and Rh to the occupied and unoccupied states. Optical properties, including absorption and reflectivity, reveal strong interaction with electromagnetic radiation, particularly in the ultraviolet region. This study highlights the methodological novelty of integrating DFT with machine learning techniques for advanced electronic structure analysis. The findings not only improve the fundamental understanding of CaRhH₃ but also demonstrate its potential suitability for hydrogen energy applications, offering both scientific and technological significance.
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