Formation and stability of different polymorphs of NaSi2 predicted from DFT calculations using high pressure-high temperature in-situ experi

In the search of new materials for energy applications based on abundant elements, intermetallic silicides based on alkaline metals will be of high interest. Using DFT calculations, we found the possibility to obtain two different polymorphs of NaSi2 at high pressure with potential for both batteries and thermoelectricity. We propose to investigate the formation under high pressure and high temperature (HP-HT) of the two different polymorphs of NaSi2 with monoclinic and cubic structures predicted to be stable at high pressure using HP-HT X-Ray diffraction at ID06-LVP ESRF beamline of the ESRF. This will also permit us to investigate their existence domain in P,T space and the pressure dependence of their volume when decreasing the pressure at room temperature. The use of large volumepress will permit us to further study these phases in our laboratory.