Stable and metastable structures of tin (IV) oxide at high pressure

We have analysed SnO2 with a combination of synchrotron X-ray diffraction and X-ray absorption spectroscopy across a pressure range of 0 & RARR;82.9 GPa with thermal annealing by a CO2 laser allowing access to all of the known high-density polymorphs of SnO2, and here report their crystallographic information. The metastability of the post-rutile & alpha;-PbO2 and PdF2 structures in SnO2 are investigated by experiment and PW-DFT simulations, revealing a complex energetic landscape and suggesting a significant dependence of the observed phases on the pressure-temperature pathway taken in experiment.This article is part of the theme issue 'Exploring the length scales, timescales and chemistry of challenging materials (Part 1)'.

Automated summary

In this study, SnO2 was analyzed using a combination of synchrotron X-ray diffraction and X-ray absorption spectroscopy across a pressure range of 0 to 82.9 GPa. By utilizing thermal annealing with a CO2 laser, access to all known high-density polymorphs of SnO2 was achieved and their crystallographic information was reported. The metastability of the post-rutile α-PbO2 and PdF2 structures in SnO2 was investigated through experiments and PW-DFT simulations, revealing a complex energetic landscape and suggesting a significant dependence on the pressure-temperature pathway taken in the experiment.