The Ce-Ni-Si System Revisited: More Homologue Compounds?
- Author(s)
- Fainan Failamani, Andriy Grytsiv, Jiri Bursik, Gerald Giester, Peter Rogl
- Abstract
The nickel-rich region of the system Ce-Ni-Si has been reinvestigated utilizing X-ray single-crystal, powder, and electron diffraction as well as electron microprobe and thermal analyses. Two novel hexagonal compounds, τ-Ce20+xNi36+ySi30-z and τ′-Ce30+xNi50+ySi42-z, were identified. The crystal structure of τ-Ce20+xNi36+ySi30-z was derived from single-crystal X-ray diffraction and found to be isotypic with the Sm10Ni20.8P15-type structure (S.G. P63/m, x = 1.8, y = 3.0, z = 1.8, a = 2.07156(2) nm, c = 0.39990(1) nm, RF = 0.048). Rietveld refinement of τ′-Ce30+xNi50+ySi42-z revealed isotypism with Tb15Ni28P21 (S.G. P63/m, a = 2.46926(13) nm, c = 0.40019(3) nm, RF = 0.058). The compound Ce3Ni4Si2 from X-ray single-crystal analysis was found to crystallize in a novel structure type with monoclinic unit cells (S.G. C2/c, a = 1.54708(3) nm, b = 0.58677(1) nm, c = 0.74331(1) nm, β = 102.985(1)°, RF = 0.017). This compound belongs to a new homologue series in the RE-Ni-Si system (RE = La and Ce) with general formula of RE(3×2n)Ni(3×2n + 1)Si(2n+1); n = 0,1, ..., ∞. The crystal structure of this series is characterized by alternating numbers (2n) of corner-sharing Si-polyhedral blocks sandwiched between zigzag nickel chains. Higher-order members of this series are produced by the formation of more corner-sharing Si-polyhedral blocks due to removal of nickel chains.
- Organisation(s)
- Department of Materials Chemistry, Department of Mineralogy and Crystallography
- External organisation(s)
- Czech Academy of Sciences, Institut Teknologi Bandung
- Journal
- Inorganic Chemistry
- Volume
- 63
- Pages
- 8604-8614
- No. of pages
- 11
- ISSN
- 0020-1669
- DOI
- https://doi.org/10.1021/acs.inorgchem.3c04594
- Publication date
- 05-2024
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 105116 Mineralogy, 105113 Crystallography
- ASJC Scopus subject areas
- Physical and Theoretical Chemistry, Inorganic Chemistry
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/5020a066-14c2-4d1c-a26f-f5be263ab669