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Antiferromagnetic Ordering (antiferromagnetic + ordering)
Selected AbstractsHydrogenation of the Ce(Rh1-xIrx)Ga System: Occurrence of Antiferromagnetic Ordering in the Hydrides Ce(Rh1-xIrx)GaH1.8.CHEMINFORM, Issue 39 2007B. Chevalier Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Antiferromagnetic Ordering with an Anisotropy Reversal in USn0.5Sb1.5.CHEMINFORM, Issue 32 2006V. H. Tran Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Antiferromagnetic Ordering in GdRhIn5.CHEMINFORM, Issue 51 2004Kazimierz Latka Abstract For Abstract see ChemInform Abstract in Full Text. [source] Thermal Decomposition Reactions as a Tool for the Synthesis of New Thermodynamic Metastable Modifications: Synthesis, Structures, and Properties of (Formato)nickel(II) Coordination Polymers Based on 4,4,-BipyridineEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 12 2010Jan Boeckmann Abstract The reaction of nickel formate with 4,4,-bipyridine (bipy) in aqueous solution at room temperature leads to the formation of the hydrated compound [Ni(HCO2)2(H2O)(bipy)·4H2O]n (1) reported recently. On heating, compound 1 decomposes into the new anhydrous compound of composition [Ni(HCO2)2(bipy)]n (2II), which decomposes on further heating. Interestingly, if the anhydrous compound is prepared from solution, a new modification 2I is obtained. Investigations on the stability of both forms show that modification 2I presents the thermodynamically most stable form between room and decomposition temperature, whereas modification 2II, which can only be prepared by thermal decomposition, is metastable. In the crystal structure of 2I, the Ni2+ cations are coordinated by four ,2 - anti,anti bridging formato anions and two bridging ,2 -bipy ligands in a slightly distorted octahedralgeometry. The formato anions bridge the metal cations in zigzag chains, which are further connected by ,2 - anti,anti formato anions and bipy ligands to give a three-dimensional coordination network. IR spectroscopic investigations on the metastable form 2II also indicate that all formato anions act as bridging ligands. Magnetic measurements of the hydrated and anhydrous compounds reveal different behavior with a ferromagnetic ordering for compound 2I and an antiferromagnetic ordering for compound 1. For form 2II, only Curie,Weiss paramagnetism was found. [source] Magnetic behaviour of synthetic Co2SiO4ACTA CRYSTALLOGRAPHICA SECTION B, Issue 6 2009Andrew Sazonov Synthetic Co2SiO4 crystallizes in the olivine structure (space group ) with two crystallographically non-equivalent Co positions and shows antiferromagnetic ordering below 50,K. We have investigated the temperature variation of the Co2SiO4 magnetic structure by means of non-polarized and polarized neutron diffraction for single crystals. Measurements with non-polarized neutrons were made at 2.5,K (below TN), whereas polarized neutron diffraction experiments were carried out at 70 and 150,K (above TN) in an external magnetic field of 7,T parallel to the b axis. Additional accurate non-polarized powder diffraction studies were performed in a broad temperature range from 5 to 500,K with small temperature increments. Detailed symmetry analysis of the Co2SiO4 magnetic structure shows that it corresponds to the magnetic (Shubnikov) group Pnma, which allows the antiferromagnetic configuration (Gx, Cy, Az) for the 4a site with inversion symmetry (Co1 position) and (0,Cy,0) for the 4c site with mirror symmetry m (Co2 position). The temperature dependence of the Co1 and Co2 magnetic moments obtained from neutron diffraction experiments was fitted in a modified molecular-field model. The polarized neutron study of the magnetization induced by an applied field shows a non-negligible amount of magnetic moment on the oxygen positions, indicating a delocalization of the magnetic moment from Co towards neighbouring O owing to superexchange coupling. The relative strength of the exchange interactions is discussed based on the non-polarized and polarized neutron data. [source] 3D Architectures of Iron Molybdate: Phase Selective Synthesis, Growth Mechanism, and Magnetic PropertiesCHEMISTRY - A EUROPEAN JOURNAL, Issue 3 2007Yi Ding Abstract Monoclinic and orthorhombic Fe2(MoO4)3 microsized particles with complex 3D architectures have been selectively prepared by a template-free hydrothermal process. The pH value, reaction time, temperature, and molybdenian source have crucial influence on the phase formation, shape evolution, and microstructures. Monoclinic Fe2(MoO4)3 particles obtained at pH,1 and pH,1.65 display ferromagnetic ordering at 10.4,K and 10.5,K, respectively, and the ferromagnetic component is determined to be 0.0458,,B and 0.0349,,B per Fe-ion at 10,K, respectively. For orthorhombic ,-Fe2(MoO4)3, antiferromagnetic ordering was observed about 12,K. At higher temperatures, ,-Fe2(MoO4)3 began to follow the Curie,Weiss law with ,=,70,K. Such 3D architectures of monoclinic and orthorhombic ,-Fe2(MoO4)3 microparticles with unique shapes and structural characteristics may find applications as catalysts and as well as in other fields. [source] | ||||||||||