Bivalent neodymium, dysprosium and thulium in solution

Solutions of hardly reducible Tm2+(E0=-2.3V) Dy2+(E0=-2.45V) and Nd2+(E0=-2.6V) lanthanides are prepared and their physicochemical properties are studied. Absorption spectra of the Nd, Dy, Tm iodide solutions in THF are analyzed. The Nd2+, Dy2+ solutions are unstable with time, while thulium (2) solutions preserve their colur in the absence of an oxidant for many days. The oxidation reaction of the Dy2+, Nd2+ and Tm2+ is a first-order reaction. The oxidation rate constants and their respective half-times of oxidation are given. Some energy parameters of the bivalent Nd, Dy and Tm in the THF are determined from the absorption spectra data