Retraction Note: Carbon enters silica forming a cristobalite-type CO₂–SiO₂ solid solution

Nature Communications 5: Article number: 3761 doi: (2014); Published 30 April 2014; Updated 29 November 2016

In this Article, we reported the synthesis of a crystalline CO₂–SiO₂ solid solution by reacting carbon dioxide and silica in a laser-heated diamond anvil cell at pressures between 16 and 22 GPa and temperatures greater than 4,000 K, and showed that carbon enters silica. We have now reanalysed all our X-ray diffraction patterns, in particular those at room pressure where potential volatile components (for example, CO₂) are absent, making data interpretation as simple and clean as possible¹. Indeed, we find that orthorhombic β-ReO₂ (Pbcn) provides a better fit to the temperature-quenched new phase than tetragonal cristobalite. This possibility was also indicated by experimental results from Santamaria-Perez and co-workers². Hence what we previously interpreted as a CO₂–SiO₂ solid solution now appears to be ReO₂, indicating the decomposition of CO₂ leading to the oxidation of Re from the gasket, which is found to diffuse into the sample in the laser heating experiment. The authors therefore wish to retract this Article.