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The phase content and sequence, the crystal structure, and the magnetic properties of perovskite solid solutions of the (1-y)BiFeO3-yBiZn0.5Ti0.5O3 series (0.05 ≤ y ≤ 0.90) synthesized under high pressure have been studied. Two perovskite phases, namely the rhombohedral R3c and the tetragonal P4mm, which correspond to the structural types of the end members, BiFeO3 and BiZn0.5Ti0.5O3, respectively, were revealed in the as-synthesized samples. The rhombohedral and the tetragonal phases were found to coexist in the compositional range of 0.30 ≤ y ≤ 0.90. Magnetic properties of the BiFe1-y[Zn0.5Ti0.5]yO3 ceramics with y < 0.30 were measured as a function of temperature. The obtained compositional variations of the normalized unit-cell volume and the Néel temperature of the BiFe1-y[Zn0.5Ti0.5]yO3 perovskites in the range of their rhombohedral phase were compared with the respective dependences for the BiFe1-yB3+ yO3 perovskites (where B3+ = Ga, Co, Mn, Cr, and Sc). The role of the high-pressure synthesis in the formation of the antiferromagnetic states different from the modulated cycloidal one characteristic of the parent BiFeO3 is discussed. [ABSTRACT FROM AUTHOR]

We report on single-crystal growth, and crystal structure of CuMn 3 As 2 and Cu 2 Mn 4 As 3 compounds. Magnetic properties of Cu 2 Mn 4 As 3 were studied in temperature range between 2 and 400 K. The single crystals were prepared from bismuth flux and characterized by means of single crystals diffraction, electron-microprobe analysis, magnetic and resistivity measurements. Crystal structures of CuMn 3 As 2 and Cu 2 Mn 4 As 3 were determined by synchrotron radiation x-ray diffraction experiments at 100 K. The CuMn 3 As 2 and Cu 2 Mn 4 As 3 crystallize in an orthorhombic structure with very similar lattice parameters. Magnetic and resistivity measurements on Cu 2 Mn 4 As 3 suggest existence of long range magnetic order below 315 K with another magnetic transition at 45 K. [ABSTRACT FROM AUTHOR]

Chain-like crystal structure of phenylacetato complex of Ce(III) elucidated by Rietveld method. Nona-coordinated Ce(III) ion (O 9 donor set) of muffin shape polyhedron. Field induced slow magnetic relaxation with direct and Raman relaxation processes. [Display omitted] [Ce(PAA) 3 (H 2 O)] n complex (1) (HPAA is phenylacetic acid) was synthesised and studied. The crystal structure of 1 was elucidated by the Rietveld method. Its crystal structure is polymeric and is built up of Ce(III) ions interconnected by bridging PAA− ligands. The Ce(III) ions in 1 are nona-coordinated by eight carboxylate oxygen atoms from six PAA− ligands, and one aqua ligand completes the coordination sphere yielding O 8 O donor set. The studied material displays field-induced slow magnetic relaxation. Temperature dependence of the relaxation time suggests the existence of direct and Raman relaxation processes. Similarly, as for the other Ce(III) complexes, the existence of Orbach process may be questioned due to the large discrepancy between the value of the energy gap obtained from static and dynamic measurements. [ABSTRACT FROM AUTHOR]

The coordination polymer [Gd(PDOA)(NO 3 )(H 2 O) 2 ] n ( 1 ) (PDOA = o -phenylenedioxydiacetato) has been prepared and spectroscopically and structurally characterized. Its crystal structure is formed of a ribbon-like arrangement of Gd(III) atoms linked by bridging carboxylate groups and placed at the cusps of fused triangles with Gd⋯Gd distances of about 6.1 Å. The Gd(III) central atoms exhibit decacoordination by oxygen atoms from hexadentate PDOA ligands with chelating and bridging functions, a chelating nitrato ligand and two aqua ligands. Intra- and intermolecular hydrogen bonds of the O H⋯O and C H⋯O types contribute to the stability of the structure. The temperature dependence of the magnetic susceptibility revealed weak magnetic interactions among Gd(III) ions which may be attributed to dipolar coupling. Investigation of the magnetocaloric effect gives an estimate of the maximum value of isothermal change of magnetic entropy –ΔS m ≈ 35 J kg −1 K −1 which suggests that 1 can be a good material for magnetic cooling at low temperatures. [ABSTRACT FROM AUTHOR]