Re-investigation of the Cd-Ce phase diagram and structural characterization of the high-temperature phase Cd_17+2xCe_2-x (x ~ 0.02)

Author(s)

Barbara Janina Skolyszewska-Kühberger, Thomas L. Reichmann, Martin C. J. Marker, Herta Silvia Effenberger, Herbert Ipser

Abstract

The complete Cd-Ce equilibrium phase diagram was investigated with a combination of powder-XRD, SEM and DTA. The presence of seven intermetallic compounds, i.e., CdCe, Cd2Ce, Cd3Ce, Cd58Ce13, Cd6Ce (resp. Cd37Ce6), Cd17Ce2 and Cd11Ce, reported previously in literature, was confirmed. A polymorphic transformation of Cd2Ce into a high-temperature modification was indicated to occur at 871 °C at the respective stoichiometric composition. The homogeneity range of both the low (γ) and high-temperature (δ) allotropic modification of Ce could be determined precisely and a limited solubility of 2.5 as well as 17 at.% Cd was derived. In addition, liquidus temperatures and all invariant reactions were examined by thermal analyses. One eutectoid reaction at 421 °C and ~15 at.% Cd as well as four eutectic reactions at ~20 at.% Cd (646 °C), 56 at.% Cd (910 °C), 77.5 at.% Cd (857 °C) and close to 100 at.% Cd (320 °C) were detected. One peritectoid reaction at 852 °C and three peritectic reactions at 730, 610 and 605 °C were recorded. Moreover, single-crystal x-ray diffraction was employed, and a complete description of the structure of Cd17+2x Ce2−x (x ~ 0.02) is given with focus on the correct defect mechanism. It turned out that vacancy formation on one of the Ce sites (Ce1) is compensated by 2 Cd atoms on Cd sites (Cd5) very close by

Organisation(s)

Department of Functional Materials and Catalysis, Department of Mineralogy and Crystallography

External organisation(s)

Karlsruher Institut für Technologie

Journal

Journal of Phase Equilibria and Diffusion

Volume

37

Pages

186-200

No. of pages

15

ISSN

1547-7037

DOI

https://doi.org/10.1007/s11669-015-0441-z

Publication date

01-2016

Peer reviewed

Yes

Austrian Fields of Science 2012

104003 Inorganic chemistry, 104011 Materials chemistry, 105113 Crystallography

Keywords

Portal url

https://ucrisportal.univie.ac.at/en/publications/reinvestigation-of-the-cdce-phase-diagram-and-structural-characterization-of-the-hightemperature-phase-cd172xce2x-x--002(5ffdca83-d6a3-4081-b060-3dab169c7076).html