In-situ high-pressure X-ray diffraction on the Zn6Sc 1/1 periodic cubic approximant to a quasicrystal
2014 (English)In: Zeitschrift fur Kristallographie, ISSN 0044-2968, Vol. 229, no 3, 230-235 p.Article in journal (Refereed) Published
The Zn6Sc 1/1 cubic approximant to a quasicrystal has been studied in-situ at high pressures by single-crystal X-ray diffraction. This phase can be described as a bcc packing of Tsai-type icosahedral clusters whose center is occupied by a disordered Zn-4 tetrahedron. At ambient pressure the Zn6Sc undergoes a structural phase transition at 159 K to a monoclinic superstructure in which the Zn-4 tetrahedra are orientationally ordered along the  direction of the high-temperature bcc phase. In the pressure range up to 35 GPa, two new superstructures have been observed. The second phase corresponds to a four-fold pseudo cubic superstructure, i.e. a very large unit cell with a lattice parameter of about 5.5 nm. The resulting pressure-temperature phase diagram is different from that of Cd6Yb, which was reported by Watanuki et al. (2006).
Place, publisher, year, edition, pages
2014. Vol. 229, no 3, 230-235 p.
quasicrystals, approximants, phase transition
IdentifiersURN: urn:nbn:se:uu:diva-224502DOI: 10.1515/zkri-2013-1684ISI: 000333868500006OAI: oai:DiVA.org:uu-224502DiVA: diva2:717067