Multimodal Structural Characterization of Ge–S–I Glasses by Combination of DFT Calculation and IR and Polarized Raman Spectroscopy
| Autor: | Frédéric Adamietz, Younes Messaddeq, Matthieu Chazot, Vincent Rodriguez, Raphaël Méreau, Mohammed El Amraoui |
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| Rok vydání: | 2019 |
| Předmět: |
010302 applied physics
Materials science Infrared Neutron diffraction 02 engineering and technology 021001 nanoscience & nanotechnology 01 natural sciences Molecular physics Spectral line Surfaces Coatings and Films Electronic Optical and Magnetic Materials Characterization (materials science) Amorphous solid symbols.namesake General Energy 0103 physical sciences Tetrahedron symbols Density functional theory Physical and Theoretical Chemistry 0210 nano-technology Raman spectroscopy |
| Zdroj: | The Journal of Physical Chemistry C. 123:3758-3769 |
| ISSN: | 1932-7455 1932-7447 |
| Popis: | From a dual experimental–theoretical vibrational analysis, we propose a new rationalized structural description of Ge–S–I chalcogenides glasses at the nanoscale. A vibrational multipolar approach based on a simultaneous deconvolution of infrared (IR) and polarized Raman spectra (RS-VV and RS-HV) has been applied on these glasses. According to recent results on the amorphous GeS2 structure by X-Ray and neutron diffraction and to our spectral analyses, we suggest that the local structure of the glass backbone is effectively described by a combination of α-GeS2 nanolayers, edge-sharing GeS4 tetrahedra (ES-Td, ca ∼50%), and corner-sharing GeS4 tetrahedra (CS-Td, ca ∼50%). We have then compared the experimental spectra to the calculated IR and polarized Raman spectra of some selected GexSyIz structural units obtained by density functional theory calculation. The stretching modes of the Ge–S–I occurring in the high frequency spectral range (300–450 cm–1) are essentially those of the GeS2 glass backbone and have... |
| Databáze: | OpenAIRE |
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