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Oxidation State and Local Structure of Chromium Ions in LaOCl

LaOCl doped with 0–10 mol% Cr was synthesized by thermal decomposition of chlorides. X-ray diffraction (XRD) analysis revealed that incorporation of chromium results in a decrease of the lattice parameter a and a simultaneous increase of the lattice parameter c. The local structure of chromium ions...

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Detalles Bibliográficos
Autores principales: Antuzevics, Andris, Krieke, Guna, Ozols, Haralds, Fedotovs, Andris, Sarakovskis, Anatolijs, Kuzmin, Alexei
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8269520/
https://www.ncbi.nlm.nih.gov/pubmed/34201933
http://dx.doi.org/10.3390/ma14133539
Descripción
Sumario:LaOCl doped with 0–10 mol% Cr was synthesized by thermal decomposition of chlorides. X-ray diffraction (XRD) analysis revealed that incorporation of chromium results in a decrease of the lattice parameter a and a simultaneous increase of the lattice parameter c. The local structure of chromium ions was studied with X-ray photoelectron (XPS), X-ray absorption (XANES), multifrequency electron paramagnetic resonance (EPR) and electron-nuclear double resonance (ENDOR) spectroscopy techniques. It was determined that synthesis in oxidizing atmosphere promotes the incorporation of chromium ions predominantly in the 5+ oxidation state. Changes of chromium oxidation state and local environment occur after a subsequent treatment in reducing atmosphere. Spin-Hamiltonian (SH) parameters for a Cr(5+) and two types of Cr(3+) centers in LaOCl were determined from the EPR spectra simulations.