Mononuclear Transition Metal Cymantrenecarboxylates as Precursors for Spinel-Type Manganites

Novel mononuclear cymantrenecarboxylate complexes of transition metals, [Co(H2O)6](CymCO2)2·4H2O (Cym = (η5-C5H4)Mn(CO)3) (1), [Ni(H2O)6](CymCO2)2·4H2O (2), [Zn(H2O)6](CymCO2)2·4H2O (3), [Co(CymCO2)2(imz)2] (imz = imidazole, 4), [Co(CymCO2)2(bpy)2]·2PhMe (bpy = 2,2′-bipyridyl, 5), [Ni(CymCO2)(bpy)2(H2O)][CymCO2]·0.5MePh·2H2O (6), [Cu(CymCO2)2(imz)2] (7), and [Cu(CymCO2)2(bpy)(H2O)] (8), were obtained and characterized by single-crystal X-ray analysis. Complexes 1–3 are isostructural. Magnetism of the Co complexes 1, 4, and 5 was studied; it was shown that they exhibit the properties of field-induced single-molecule magnets with magnetization reversal barriers (ΔE/kB) of 44, 13, and 10 K, respectively. Thermal decomposition of complexes 1–8 was studied by means of DSC and TGA methods. The final products of thermolysis of 1–6 in air, according to powder XRD data, are the pure spinel phases MMn2O4; for the cases of copper complexes, the mixtures of CuMn2O4 and CuO were found in the products

Something You Need Might Be under Your Feet: Molecular Magnetism of Heavy Kramers Lanthanide Hydrated Chlorides and Their Complexes with Polydentate Terpy Ligand

A study of the molecular magnetism of the hydrated salts [Ln(H2O)6Cl2]Cl (Ln = Gd (1Gd), Dy (1Dy), Er (1Er), Yb (1Yb)) and lanthanide chloride complexes with 2,2′;6′,2″-terpyridine (terpy) synthesized on their basis, [Ln(H2O)4(terpy)Cl]Cl2·3H2O (Ln = Gd (2Gd), Dy (2Dy), Er (2Er), and Yb (2Yb), was carried out. It was found that both the initial hydrated chlorides containing Dy, Er, Yb, and their derivatives with terpyridine exhibit the properties of single-molecule magnets. For the complexes with terpyridine, the values of the remagnetization barriers increase from Er to Dy, while for the aquachlorides, the corresponding values increase in the series Ueff (1Dy) eff (1Er). It was found that magnetic relaxation in Yb complexes mostly proceeds according to the Raman mechanism

Synthesis, structure, and physical properties of new rare earth ferrocenoylacetonates

New ferrocenoylacetonate complexes of several rare earth elements, [Ln(fca)3(bpy)]·MeC6H5 (Ln = Pr (1), Eu (2), Gd (3), Tb (4), Dy (5), Ho (6), Y (7); bpy – 2,2’-bipyridine; Hfca – FcCOCH2COMe) as well as scandium ferrocenoylacetonate [Sc(fca)3]·0.5MeC6H5 (8), were synthesized and characterized by single crystal X-ray diffraction analysis. In the crystal lattice of the isostructural complexes 1–7, two [Ln(fca)3(bpy)] molecules form a pair due to stacking interactions between the bpy ligands. The Ln3+ ions are coordinated in a square antiprism geometry with a coordination number of 8. The Sc3+ ions in complex 8 are coordinated in an octahedral geometry. Thermolysis of complexes 1–7 was studied under air and argon atmospheres; in the first case, it affords perovskites LnFeO3 as one of the products. Complexes 4–6 display single-molecule magnet properties, and the effective relaxation barrier for the Dy complex 5, was found to be Δeff/kB = 241 K, which is one of the highest values obtained for a mononuclear β-diketonate lanthanide complex

Novel mononuclear and 1D-polymeric derivatives of lanthanides and (η6-benzoic acid)tricarbonylchromium: synthesis, structure and magnetism:synthesis, structure and magnetism

Novel derivatives of lanthanides and (η6-benzoic acid)tricarbonylchromium were synthesized and characterized; complexes of Tb, Dy, Er and Yb exhibit SMM behavior.</p

CCDC 1499075: Experimental Crystal Structure Determination

Related Article: Andrey Gavrikov, Pavel Koroteev, Andrey Ilyukhin, Nikolay Efimov, Andreas K. Kostopoulos, Aleksandr Baranchikov, Aleksandr Tyurin, Denis Kirdyankin, Konstantin Gavrichev, Floriana Tuna, Zhanna Dobrokhotova|2017|Polyhedron|122|184|doi:10.1016/j.poly.2016.11.02

CCDC 1519459: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures

CCDC 1519457: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures

CCDC 1519458: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures