Naslov
1D Heterometallic Oxalate Compounds as Precursors for Mixed Ca–Cr Oxides – Synthesis, Structures, and Magnetic Studies

Autori
Androš, Lidija ; Jurić, Marijana ; Popović, Jasminka ; Pajić, Damir ; Zadro, Krešo ; Molčanov, Krešimir ; Žilić, Dijana ; Planinić, Pavica

Izvornik
European journal of inorganic chemistry (1434-1948) (2014), 33; 5703-5713

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
heterometallic complexes; calcium; chromium; oxides; magnetic properties

Sažetak
The heterodimetallic compounds {; ; ; [CaCr2(L)2(C2O4)4]·xH2O}; ; ; n [L = 2, 2′-bipyridine (bpy), x = 0.83 (1) ; L = 1, 10-phenanthroline (phen), x = 0.33 (2)] were synthesized and characterized by IR spectroscopy, X-ray diffraction and magnetic measurements. The crystal structure of 2 is reported: the chelation of a [Cr(phen)(C2O4)2]– units towards Ca cations results in 1D double zigzag chains. The ability of 1 and 2 to act as single-source precursors for the formation of Ca–Cr oxides is explored by thermal analysis, powder X-ray diffraction and IR spectroscopy. The thermal processing of 1 and 2 at 1100 °C in air led to the appearance of the β-CaCr2O4 phase as the major crystalline oxide. By heating the samples up to 1100 °C in nitrogen, only the β-CaCr2O4 phase formed, whereas heating at 1400 °C caused the crystallization of two polymorphs, α- and β-CaCr2O4. The magnetic behaviour of β-CaCr2O4 pointed to the freezing of magnetic moments in coexistence with a weak ferromagnetic order.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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