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1. Elasticity of Hydrated Al-Bearing Stishovite and Post- Stishovite: Implications for Understanding Regional Seismic VS Anomalies Along Subducting Slabs in the Lower Mantle

   Zhang, Y. ( April 2022 , Journal of geophysical research Solid earth)
2. High thermal conductivity of stishovite promotes rapid warming of a sinking slab in Earth's mantle

   https://doi.org/10.1016/j.epsl.2022.117477  

   Hsieh, Wen-Pin ; Marzotto, Enrico ; Tsao, Yi-Chi ; Okuchi, Takuo ; Lin, Jung-Fu ( April 2022 , Earth and Planetary Science Letters)
3. Atomistic insight into the ferroelastic post-stishovite transition by high-pressure single-crystal X-ray diffraction

   https://doi.org/10.2138/am-2022-8458  

   Zhang, Yanyao ; Chariton, Stella ; He, Jiaming ; Fu, Suyu ; Xu, Fang ; Prakapenka, Vitali B. ; Lin, Jung-Fu ( January 2023 , American Mineralogist)

   Abstract The post-stishovite transition is a classic pseudo-proper typed ferroelastic transition with a symmetry-breaking spontaneous strain. This transition has been studied using high-pressure spontaneous strains, optic modes, and elastic moduli (Cij) based on the Landau modeling, but its atomistic information and structural distortion remain poorly understood. Here we have conducted synchrotron single-crystal X-ray diffraction measurements on stishovite crystals up to 75.3 GPa in a diamond-anvil cell. Analysis of the data reveals atomic positions, bond lengths, bond angles, and variations of SiO6 octahedra across the transition at high pressure. Our results show that the O coordinates split at ~51.4 GPa, where the apical and equatorial Si-O bond lengths cross over, the SiO6 octahedral distortion vanishes, and the SiO6 octahedra start to rotate about the c axis. Moreover, distortion mode analysis shows that an in-plane stretching distortion (GM1+ mode) occurs in the stishovite structure at high pressure while a rotational distortion (GM2+ mode) becomes dominant in the post-stishovite structure. These results are used to correlate with elastic moduli and Landau parameters (symmetry-breaking strain e1–e2 and order parameter Q) to provide atomistic insight into the ferroelastic transition. When the bond lengths of two Si-O bonds are equal due to the contribution from the GM1+ stretching mode, C11 converges with C12, and the shear wave VS1[110] polarizing along [110] and propagating along [110] vanishes. Values of e1–e2 and Q are proportional to the SiO6 rotation angle from the occurrence of the GM1+ rotational mode in the post-stishovite structure. Our results on the pseudo-proper type transition are also compared with that for the proper type in albite and improper type in CaSiO3 perovskite. The symmetry-breaking strain, in all these types of transitions, arises as the primary effect from the structural angle (such as SiO6 rotation or lattice constant angle) and its relevant distortion mode in the low-symmetry ferroelastic phase. 

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4. Stishovite formation at very low pressures in soda-lime glass

   https://doi.org/10.1016/j.scriptamat.2019.06.005  

   Pozuelo, Marta ; Lefebvre, Joseph ; Srivastava, Pratyush ; Gupta, Vijay ( October 2019 , Scripta Materialia)
5. Stishovite nucleation at low shock pressures in soda-lime glass

   https://doi.org/10.1016/j.actamat.2021.117124  

   Srivastava, Pratyush ; Tanaka, Koichi ; Ramirez, Brian ; Gupta, Vijay ( August 2021 , Acta Materialia)