Modulation of optical absorption in m-Fe1−xRuxS2 and exploring stability in new m-RuS2
Autor: | B. Thapa, K. Labar, N. Limbu, Amel Laref, Raj Kumar Thapa, H. Joshi, A. Shankar, M. Ram, D. P. Rai |
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Jazyk: | angličtina |
Rok vydání: | 2021 |
Předmět: |
Materials science
Band gap Mathematics and computing Science 02 engineering and technology engineering.material 010402 general chemistry 01 natural sciences Molecular physics Article Phase (matter) Dispersion (optics) Marcasite Absorption (electromagnetic radiation) Mulliken population analysis Multidisciplinary Physics 021001 nanoscience & nanotechnology 0104 chemical sciences Crystal field theory engineering Medicine 0210 nano-technology Ground state |
Zdroj: | Scientific Reports, Vol 11, Iss 1, Pp 1-13 (2021) Scientific Reports |
ISSN: | 2045-2322 |
Popis: | A first-principle computational method has been used to investigate the effects of Ru dopants on the electronic and optical absorption properties of marcasite FeS2. In addition, we have also revealed a new marcasite phase in RuS2, unlike most studied pyrite structures. The new phase has fulfilled all the necessary criteria of structural stability and its practical existence. The transition pressure of 8 GPa drives the structural change from pyrite to orthorhombic phase in RuS2. From the thermodynamical calculation, we have reported the stability of new-phase under various ranges of applied pressure and temperature. Further, from the results of phonon dispersion calculated at Zero Point Energy, pyrite structure exhibits ground state stability and the marcasite phase has all modes of frequencies positive. The newly proposed phase is a semiconductor with a band gap comparable to its pyrite counterpart but vary in optical absorption by around 106 cm−1. The various Ru doped structures have also shown similar optical absorption spectra in the same order of magnitude. We have used crystal field theory to explain high optical absorption which is due to the involvement of different electronic states in formation of electronic and optical band gaps. Lӧwdin charge analysis is used over the customarily Mulliken charges to predict 89% of covalence in the compound. Our results indicate the importance of new phase to enhance the efficiency of photovoltaic materials for practical applications. |
Databáze: | OpenAIRE |
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