Crystal-structure properties and the molecular nature of hydrostatically compressed realgar

  title={Crystal-structure properties and the molecular nature of hydrostatically compressed realgar},
  author={Clivia Hejny and Raffaela Sagl and Daniel M. T{\"o}bbens and Ronald Miletich and Manfred Wildner and Lutz Nasdala and Angela Ullrich and Tonci Balic-Zunic},
  journal={Physics and Chemistry of Minerals},
The structure of realgar, As4S4, and its evolution with pressure have been investigated employing in situ X-ray diffraction, optical absorption and vibrational spectroscopy on single-crystal samples in diamond-anvil cells. Compression under true hydrostatic conditions up to 5.40 GPa reveals equation-of-state parameters of V0 = 799.4(2.4) Å3 and K0 = 10.5(0.4) GPa with $$K_0^\prime$$ = 8.7. The remarkably high compressibility can be attributed to a denser packing of the As4S4 molecules with… 

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