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Low-Energy Linear Structures in Dense Oxygen: Implications for the $ε$-phase

J. B. Neaton·N. W. Ashcroft
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Abstract

Using density functional theory implemented within the generalized gradient approximation, a new non-magnetic insulating ground state of solid oxygen is proposed and found to be energetically favored at pressures corresponding to the $ε$-phase. The newly-predicted ground state is composed of linear herringbone-type chains of O$_2$ molecules and has {\it Cmcm} symmetry (with an alternative monoclinic cell). Importantly, this phase supports IR-active zone-center phonons, and their computed frequencies are found to be in broad agreement with recent infrared absorption experiments.

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J. B. Neaton, N. W. Ashcroft. 2002-01-27. Low-Energy Linear Structures in Dense Oxygen: Implications for the $ε$-phase. https://doi.org/10.1103/physrevlett.88.205503

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