There has been considerable interest in the complexes formed by the lanthanides with various monodentate neutral ligands with O as the donor atom. Phosphine oxides, in particular, have proven useful in complexing to lanthanide metal ions and have found practical application in the solvent extraction and separation of lanthanides.1 Several lanthanide(III) nitrate complexes with triphenylphosphine oxide (OPPh3) have been prepared resulting in complexes having as few as two and as many as four OPPh3 groups per lanthanide center.2−4 An earlier study by Cousins and Hart5 identified the complex [Nd(OPPh3)3(NO3)3]. Two crystal phases of this same complex were briefly reported later by Mascarenhas et al., 6 but no structural data was given. A complete structural analysis of a third phase of the complex [Nd(OPPh3)3(NO3)3] is reported below.
Gary, J. Brannon, ""A new phase of the complex trinitratotris(triphenylphosphineoxide)neodymium(lll)" (2004). Faculty Publications. 74.