Observation of an O8 molecular lattice in the ɛ phase of solid oxygen

  title={Observation of an O8 molecular lattice in the ɛ phase of solid oxygen},
  author={Lars F Lundegaard and G. Weck and Malcolm I McMahon and Serge Desgreniers and Paul Loubeyre},
Of the simple diatomic molecules, oxygen is the only one to carry a magnetic moment. This makes solid oxygen particularly interesting: it is considered a ‘spin-controlled’ crystal that displays unusual magnetic order. At very high pressures, solid oxygen changes from an insulating to a metallic state; at very low temperatures, it even transforms to a superconducting state. Structural investigations of solid oxygen began in the 1920s and at present, six distinct crystallographic phases are… 

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