Cristina Rosu

X-ray structure of dodecasodium tricopper(II)bis[nonatungstabismuthate(III)] hydrate, a polyoxometalate salt containing α-B-BiW9O33 units

The reaction of [Bi2W22O74(OH)2]12− with Cu2+ in hot aqueous solution in the presence of Na+ affords the polyoxometalate salt Na12[Cu3Bi2W18O66]⋅32H2O. Single-crystal X-ray analysis [monoclinic, space-group C2/m, a = 33.082(6) Å, b = 19.615(5) Å, c = 14.885(2) Å, β = 90.632(12)°, Z = 4; R(F) = 0.065 for 6029 data with I>σ (I), wR(F2) = 0.135 for all 8793 independent reflections] shows that the anion [{Cu(H2O)}3{BiW9O33}2]12−, on a crystal mirror-plane, has noncrystallographic symmetry close to D3h. Two B-α-[BiIIIW9O33]9− units are linked by an equatorial belt of three Cu(H2O)2+ units. Three Na(H2O)2+ units are also attached in the equatorial plane. The bond geometry is square-pyramidal about each Cu atom and trigonal–prismatic about each Na.

Cobalt(II) trisodium hexamolybdoperiodate tetradecahydrate

In the title salt, CoNa 3 [IMo 6 O 24 ].14H 2 O, the anion has the Anderson structure with crystallographic 3m symmetry. The unique cation site is occupied by disordered Na + and Co 2+ ions. The I-O bond length is 1.890 (4) A. There are three types of Mo-O distances at 1.711 (4), 1.933 (2) and 2.352 (3) A, corresponding to terminal O atoms, O atoms bridging to other Mo 6+ ions and those bridging to I 7+ ions, respectively. The anions form layers perpendicular to the c axis which are separated by double layers of cations.

Synthesis, Characterization and Electrochemistry of Cobalt(II) and Copper(II) Complexes of Bismutho(III)Polyoxotungstate Ligand Anion

Abstract Cobalt(II) and copper(II) complexes with the [Bi2W22O76]14- ligand anion of the general formula [Bi2M2W20O70(H2O)6]10- (where M = CO2+, CU2+) have been prepared by the reaction of the corresponding metal salts with the [Bi2W22O76)14- ligand anion in aqueous solution at pH = 4.7. The structure of the complexes has been elucidated on the basis of IR, electronic and EPR spectral data, magnetic properties, electrochemical studies and X-ray powder diffraction.

Disodium chromium(III) hexamolyb­do­iodate(VII) 24‐hydrate, Na2Cr[IMo6O24]·24H2O

The title compound can be formulated as [Cr(H2O)6][Na2(H2O)10][IMo6O24]·8H2O. The anion has the I atom on an inversion centre and has close to \overline 3m symmetry, with I—O bond lengths in the range 1.881–1.890 (2) A and Mo—O bond lengths in the ranges 1.697 (3)–1.714 (3), 1.915 (2)–1.948 (2) and 2.317 (2)–2.357 (2) A.

Interaction of Cobalt(II) and Copper(II) with Polyoxometallates. Structure of Na3Co[IMo6O24]. 14H2O

Abstract Cobalt(H) and copper(II) complexes with the ligand anion [IMo6O24]5 (periodate 6-molybdoanion) of the general formula Na3M[IMo6O24).nH2O (where M = Co, Cu) have been prepared by the reaction of the corresponding metal salts with the ligand in aqueous media (pH = 6). The complexes were characterised by elemental and thermo-gravimetric analyses, spectral data (IR, UV-vis). The EPR spectrum of a copper(II) powder sample was recorded at both room temperature and 12 K indicating a weakly distorted octahedral copper(II) stereochemistry. The crystal structure of Na3Co[IMo6O24].14H2O has been determined by single-crystal X-ray diffraction technique.