2023/09/25 by Elatresh, Sabri F., Askarpour, V., Bonev, S. A.
#FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci)
paper · doi:10.48550/arxiv.2309.13936
The structure of solid oxygen has been studied at pressures from 50 to 140~GPa using static structure search methods and molecular dynamics simulations with density functional theory and a hybrid exchange functional. Several crystalline structures with space group symmetries \it Pnma, \it P 21\it /m, \it Pm and \it P 63/\it mmc have been identified as candidates for the ζ phase of oxygen at 0~K. Within the hybrid exchange functional framework and at 300~K temperature, \it Pm is shown to be energetically most favorable above 111~GPa. A comparison with experimental X-ray diffraction, spectroscopic and superconductivity measurements is provided for all competing structures.