Ab initio thermal expansion and thermoelastic properties of ringwoodite (&amp;lt;i&amp;gt;γ&amp;lt;/i&amp;gt;-Mg&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt;SiO&amp;lt;sub&amp;gt;4&amp;lt;/sub&amp;gt;) at mantle transition zone conditions
European journal of mineralogy