Pressure-Induced Structural transformations of the Zintl phase sodium silicide
نویسندگان
چکیده
The high-pressure behaviour of NaSi is studied using Raman spectroscopy and angle-dispersive synchrotron X-ray diffraction to observe the onset of structural phase transformations and potential oligomerisation into anionic Si nanoclusters with extended dimensionality. Our studies reveal a first structural transformation occurring at 8-10 GPa, followed by irreversible amorphisation above 15 GPa, suggesting the formation of Si-Si bonds with oxidation of the Si species and reduction of Na to metallic sodium. We have combined our experimental studies with DFT calculations to assist in the analysis of the structural behaviour of NaSi at high pressure.
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