Amorphous zircon at high pressure


Journal of Physics and Chemistry of Solids, vol.153, 2021 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 153
  • Publication Date: 2021
  • Doi Number: 10.1016/j.jpcs.2021.109991
  • Journal Name: Journal of Physics and Chemistry of Solids
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Chemical Abstracts Core, INSPEC, Metadex
  • Keywords: Amorphous, ZrSiO4, High pressure
  • Karadeniz Technical University Affiliated: Yes


© 2021 Elsevier LtdThe high-pressure behavior of a very low-density amorphous zircon model having Zr (Si) coordination of 5.6 (4.02) is explored by ab initio simulations. Two consecutive pressure-induced phase modifications are proposed for this material. The first transition is from a very low-density amorphous state to a dense amorphous state having Zr (Si) coordination of 7.3 (4.5). The second one is from the dense phase to a high-density amorphous structure with Zr and Si coordination numbers of about 8 and 5.5, correspondingly. Both phase changes proceed progressively. The first phase transformation is irreversible whist the second one is reversible. The Voronoi polyhedron analysis reveals the presence of polyhedron of the zircon crystal (<0,4,4,0>), the zirconia baddaliyette phase (<1,3,3,0>) and the zirconia cotunnite state (<0,3,6,0>) around Zr atoms in the amorphous states formed on both compression and decompression, meaning that the amorphous configurations consist of a mixed state of them.