Bis(pentamethylene)urea complexes of the lanthanide nitrates: synthesis, characterization, properties

Lanthanide nitrate. complexes of bis(pentamethylene)urea (BPMU) with general formula Ln(NO3)(3)3BPMU, where Ln: La, Nd, Sm, Eu, Ho and Er have been prepared and characterized based on CHN elemental analyses, lanthanide titration with EDTA, molar conductivity, spectroscopic data and thermal studies. The infrared spectra show that ligands (BPMU) are bonded through the carbonyl oxygen, nitrate counter-ions are bidentate linked to the central ions. The structure of the neodymium complex was determined. The crystal is monoclinic, P2(1)/c, Z = 4, with the following parameters: a = 10.148(1) Angstrom, b = 21.879(2), c = 19.154(2) Angstrom, beta = 104.11(1)degrees, V = 4124.3(7) Angstrom(3). The polyhedron is a distorted tricapped trigonal prism, coordination number nine. (C) 2003 Elsevier Science (USA). All rights reserved.