Ab-initio structural search in solid oxygen at high pressure: from zero to finite temperature

[摘要] The crystal structure of solid oxygen in the terapascal (TPa) regime has been investigated with Density Functional Theory and the Random Search algorithm at zero temperature. We also considered the effect of the entropy at finite temperatures using the QuasiHarmonic Approximation, and we found that the regime of stability of solid oxygen differs strongly from the results predicted at zero temperature. Finally, we provide some insights of oxygen as a chalcogen element.

[发布机构] Universidad de Cartagena, Cartagena de Indias, Bolívar, Colombia^1;Abdus Salam ICTP, Trieste, Italy^2

[效力级别] 化学

[关键词] Ab initio;Chalcogen elements;Finite temperatures;High pressure;Random search algorithm;Solid oxygen;Zero temperatures