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[en] Sodium triaqua[(1,2-ethanediyldinitrilo-κ2N,N')tetraacetato-κ4O1,O2,O3 ,O4]lanthanate(III) pentahydrate, Na[La(C10H12N2O8)(H2O)3].5H2O, sodium t triaqua[(1,2-ethanediyldinitrilo-κ2N,N')tetraacetato-κ4O1,O2,O3 ,O4]-neodymate(III) pentahydrate, Na[Nd(C10H12N2O8)-(H2O)3].5H2O, and sodium triaqua[(1,2-ethanediyldinitrilo-κ2N,N')tetraacetato-κ4O1,O2,O3 ,O4]europate(III) pentahydrate, Na[Eu(C10H12N2O8)(H2O)3].5H2O, are isomorphous and isostructural; all contain nine-coordinate lanthanoid ions, each of which bonds to two N atoms, four acetate O atoms and three water molecules. (orig.)
[en] The complexes of the type Cs2MCl4 (where M = Fe, Co, Ni, Cu, Zn and Mg) have distorted tetrahedral structure. Varied distortion from regular tetrahedral geometry is due to the covalent bonding between Cs-Cl. The species [MCl4]2- ions act as double faced bidentate ligands. The structure has been substantiated by IR spectra and crystal structure data. (author). 14 refs., 3 tabs
[en] μSR spectra from a metal carbonyl compound are reported for the first time. The metal cluster compound Cs2[Os10C(CO)24] shows a temperature dependent signal for implanted muons with the onset of motional narrowing at ca. 200 K. Also observed is a probable change in the width within the temperature range 40-140 K. A tentative assignment is provided for the muon sites. (orig.)
[en] The new compounds LiK[C(CN)3]2 and Li[C(CN)3] . 1/2 (H3C)2CO were synthesized and their crystal structures were determined. Li[C(CN)3] . 1/2 (H3C)2CO (H3C)2CO crystallizes in the orthorhombic space group Ima2 (no. 46) with the cell parameters a=794.97(14), b=1165.1(2) and c=1485.4(3) pm, while LiK[C(CN)3]2 adopts the monoclinic space group P21/c (no. 14) with the cell parameters a=1265.7(2), b=1068.0(2) and c=778.36(12) pm and the angle β=95.775(7) . Single crystals of K[C(CN)3] were also acquired, and the crystal structure was refined more precisely than before corroborating earlier results.
[en] This work deals with the study of norbadione A, a pigment extracted from mushrooms and known to complex cesium cations. The study of the acid-base properties of norbadione A has allowed to determine the relative acidity of the seven protonable functions of the molecule and to reveal a reversible isomerization of the double exocyclic bond of the pulvinic moieties. The observed change of configuration is induced by a hydrogen bond of the H-O-H type and by electrostatic interactions. Moreover, the microscopic protonation mechanism of the norbadione A has been analyzed, considering three different study media where the acid-base properties of the norbadione A are compared. In the presence of 0.15 mol.l-1 of NaCl, it has been observed a remarkable cooperativity in the protonation of the enol groups. At last, the use of different analytical methods (NMR, potentiometry and calorimetry) has allowed to study the complexing properties of the norbadione A towards cesium and other alkaline and rare earth cations. (O.M.)
[en] Aquanitrilotris(methylenephosphonato)dirubidium is a 3D coordination polymer with a layer structure. Space group , Z = 2; a = 8.0380(3) Å, b = 9.0522(4) Å, and c = 10.7837(4) Å; α = 113.252(4)°, β = 105.391(3)°, and γ = 96.182(3)°. Rb atoms populate two symmetrically inequivalent positions with c.n. = 8 and 10; significant difference in O–Rb–O angles in the coordination polyhedra is indicative of the ionic type of Rb–O bonds. In the crystal packing, molecules are connected by not only coordination bonds but hydrogen bonds as well.