Search for Routes to Prepare Monovalent Thulium

The effective magnetic moments (µ eff ) of the prepared solid mixtures are used to determine the presence of monovalent thulium in the reaction products. Potassium does not react with thulium diiodide TmI 2 on heating to 680°C. Under the same conditions, the backward reaction of thulium with KI occurs easily to form metallic potassium and a mixture of thulium iodides TmI x ( x = 1, 2). For the product obtained after heating Tm and KI for 1 h, µ eff corresponds to a mixture of 70% Tm (metal), 20% TmI 2 , and 10% TmI. The reduction of TmI 2 to TmI occurs in the reaction with NdI 2 . For a mixture of iodides obtained at 700°C, µ eff (3.2 μ B ) corresponds to the following contents: 10% Tm (metal), 1% TmI 2 , 44% TmI, 44% NdI 3 , and 1% NdI 2 . Iodide TmI cannot be isolated from the obtained mixtures. However, the presence of highly reactive species in the products is confirmed by the reaction of tetrahydrofuran (THF) with the product of the reaction of thulium with potassium iodide. The reaction occurs at room temperature and is accompanied by the release of hydrogen and formation of unidentified derivatives of cleaved THF. The initial substances (Tm, KI) and possible products (TmI 2 , TmI 3 , and metallic K), except for TmI, do not react with THF under the conditions used.