Crystal and molecular structures of two europium(III) nitrate complexes with triphenylphosphine oxide

The X-ray structures of the complexes Eu(NO3)(Ph3PO)3(acetone)2 (A) (Ph3PO = triphenylphosphine oxide) and Eu(NO3)3(Ph3PO)2(ethanol) (B) have been solved by the heavy-atom method, by using the three-dimensional Patterson-Fourier synthesis. The crystals are both monoclinic and belong to the space group P21/n, with Z = 4. The cell dimensions are: a = 27.825(4) Å, b = 19.422(4) Å, c = 11.238(2) Å, β = 94.9(3)° for A; and a = 22.193(4) Å, b = 10.866(2) Å, c = 17.101(3) Å, β = 105.6(3)° for B. In both complexes the europium(III) ion is ennea-coordinated to three chelate nitrate groups and three oxygens of the Ph3PO ligands for A and two of the Ph3PO and one of the ethanol for B. The acetone molecules of A are outside the coordination sphere of the metal and disordered.