Complexes of lanthanoid methanesulfonates (MS) with pyridine-N-oxide (pyO)

Lanthanoid methanesulfonate complexes of general formula Ln(MS)3.2pyO (Ln = La-Tm, Y) were synthesized and characterized. They present a non-electrolytic behaviour, forming only one isomorphous series. The MS- anion is probably bidentate and the organic ligand is bonded through the oxygen. The nephelauxetic parameter, covalent factor and Sinha's parameter and the oscillator strength in methanolic solution were calculated from the electronic spectra. A C3v symmetry and a bicaped trigonal prism geometry were concluded from the emission spectrum of the europium compound. The crystal-field parameters Bqk were also calculated. (orig.)