SCANDIUM HYDRIDE

Description

Scandium hydride, also known as scandium- hydrogen alloy, is an alloy formed by combining scandium and hydrogen. This phase can dissolve as much as 6.30% hydrogen. Scandium trihydride is an unstable molecular compound with the chemical formula ScH3. It has been produced as one of a number of other molecular scandium hydride products at low temperature employing laser ablation and characterized by infrared spectroscopy. Scandium trihydride is a quasitrigonal planar molecule with three equivalent Sc-H bonds. It has a (C3v) structure with an equilibrium distance between Sc and H of 182.0 pm and the bond angle is 119.2°. By weight percent, the composition of scandium trihydride is 6.30% hydrogen and 93.70% scandium. In scandium trihydride, the formal oxidation states of H and Sc are 21 and 13, respectively, since the electronegativity of scandium is lower than that of hydrogen.

Chemical Properties

Scandium reacts with hydrogen on heating to 573K forming compound of formula ScH3 which is not stoichiometric. Its exact composition depends upon the temperature and the pressure of the hydrogen. Scandium hydride is salt-like hydride containing the H- ion. It reacts with water liberating hydrogen.