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arXiv · 1809.08202

Physical properties of spinel-type superconductors CuRh2S4 and CuRh2Se4: A DFT study

Abstract

The structural, elastic, electronic, Vickers-Hardness, vibrational, Optical and thermodynamical properties of potentially technologically significant superconductors CuRh2S4 and CuRh2Se4 have calculated using density functional theory (DFT) with CASTEP code.The calculated lattice parameters and other properties have compared with available experimental values and found good agreement with them.The valence band and conduction bands overlapped each other at the Fermi level indicates the metallic conductivity of CuRh2S4 and CuRh2Se4. The density of states shows that S-3p and Se-4p states are more effective at the Fermi level.The charge density difference maps indicates the Cu-Rh bonds are stronger than Cu-S. The overall higher discussion notifies that the chemical bonding can be designated as an effective anisotropic connection between ionic, covalent and metallic interactions for CuRh2S4 and CuRh2Se4.The Vickers-Hardness indicates the soft material with comparing to Diamond and suitable to use wires and ribbon cables. The electron- and hole-like sheets make the complex multisheet Fermi surface of CuRh2S4. The different optical functions are also observed clearly.The absorption spectra indicate that CuRh2S4 is more suitable to use in solar cell rather than CuRh2Se4. The reflectivity spectrum shows that these compounds have the potential to be used a reflector material. Debye temperature indicates that CuRh2S4 and CuRh2Se4 should have advantages to use as a thermal barrier coating (TBC) material.The electron-phonon coupling constant indicates the phonon-mediated medium coupled BCS superconductors. The obtained potential results in present calculation could provide a significant movement for future studies.

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BibTeXRIS

Md. Ibrahim Kholil, Md. Tofajjol Hossen Bhuiyan. 2018-09-21. Physical properties of spinel-type superconductors CuRh2S4 and CuRh2Se4: A DFT study. https://arxiv.org/abs/1809.08202

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