Record details

    Fe2O3-Cr2O3 system revised
    Bezdička, Petr
    Dědeček, Jiří
    Grygar, Tomáš
    Petrovský, Eduard
    Schneeweiss, Oldřich
Publication type
    článek v odborném periodiku
Source title - serial
    Ceramics - Silikáty
    Roč. 47, č. 1
    s. 32-39
    Projekt: GA205/00/1349, GA ČR3cav_un_auth*0007298
    Projekt: GV202/98/K002, GA ČR3cav_un_auth*0011781
    Projekt: LN00A028, GA MŠk3cav_un_auth*0027909
    Projekt: ME 209, GA MŠk3cav_un_auth*0028326
    Rozsah: 8 s.
    Výzkumný záměr: CEZ:AV0Z3012916
    Výzkumný záměr: CEZ:AV0Z4032918
Subject category
    iron oxide
    solid solutions
    Vegard law
Abstract (in english)
   Hematite (a-Fe2O4) and eskolaite (Cr2O3) are typical examples of isostructural oxides with non-linear change of the lattice parameters in their solid solutions. This series was synthesized and characterized by X-ray and neutron powder diffraction, and Mossbauer and electronic spectroscopies. A region of the d-d electron transition of Fe(III) ions in near IR region (about 1000 nm) were found to be suitable for the solid solution characterization, because the transition does not suffer from strong overlaps of Fe(III) and Cr(III) transitions in electronic spectra in the Vs spectral range. Lattice parameters, verified by the comparison to data available in literature, showed that in several cases in the last decade solids of questionable quality were obtained and discussed in the hematite-eskolaite system. Neither X-ray nor neutron diffraction indicated cation ordering, hypothesized in two reports in 1990's.
   Magnetic structure of the solid solution at 0 < x < 0.6, where x = Cr/(Cr + Fe), is similar to that of hematite, but a different, yet unidentified magnetic ordering involving Fe(III) ions is established in solid solution x = 0.8 below its Neel temperature (about 150 K).
    AV ČR Brno, Geofyzikální ústav
Contributor code
    AV ČR, GFÚ
Source format
Import date
    9. 12. 2013