Complexity of the KNa.sub.2./sub.ZrF.sub.7./sub., KNa.sub.2./sub.HfF.sub.7./sub., and KNa.sub.2./sub.(Hf,Zr)F.sub.7./sub. compounds

0586032 - FZÚ 2025 RIV NL eng J - Journal Article
Matselko, O. - Poupon, Morgane - Samoľová, Erika - Vasková, Z. - Kubíková, B. - Netriova, Z. - Mičušík, M. - Boča, M.
Complexity of the KNa₂ZrF₇, KNa₂HfF₇, and KNa₂(Hf,Zr)F₇ compounds.
Journal of Solid State Chemistry. Roč. 334, June (2024), č. článku 124655. ISSN 0022-4596. E-ISSN 1095-726X
Institutional support: RVO:68378271
Keywords : crystal structure * DSC * fluoride * hafnium * phase transition * zirconium
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 3.3, year: 2022
Method of publishing: Open access

New mixed-cation fluorides KNa2HfF7 and KNa2(Hf,Zr)F7 together with isostructural KNa2ZrF7 have been synthesised in aqueous solutions and structurally characterised at room temperature by powder and single-crystal X-ray diffraction. The solid-solid phase transformations have been revealed during the differential scanning calorimetry experiments and further confirmed by temperature-dependent X-ray powder diffraction. It has been found that mixed-cation phases KNa2ZrF7, KNa2HfF7 and KNa2(Hf,Zr)F7 undergo irreversible phase transformations, which can be explained by their decomposition over 673 K. XPS analysis confirmed the presence of exclusively terminated fluorines around the transition metals and the absence of oxygen impurities in the crystal structures of compounds.
Permanent Link: https://hdl.handle.net/11104/0353639