Scandium nitrate

Scandium(III) nitrate, Sc(NO3)3, is an ionic compound. It is an oxidizer, as all nitrates are. The salt is applied in optical coatings, catalysts, electronic ceramics and the laser industry.

Preparation
Scandium nitrate can be prepared by the reaction between scandium metal with dinitrogen tetroxide.


 * Sc + 3 N2O4 → Sc(NO3)3 + 3 NO

The anhydrous form can also be obtained by the reaction between scandium chloride and dinitrogen pentoxide. The tetrahydrate can be obtained from the reaction between scandium hydroxide and nitric acid.

Properties
Scandium nitrate is a white solid which dissolves in water and ethanol. It has multiple hydrated forms, including the dihydrate, trihydrate, and tetrahydrate. The tri- and tetrahydrate exist in the monoclinic crystal system. Upon heating in air to 50 °C, the tetrahydrate transforms into the dihydrate, which at 60 °C further converts to Sc4O3(NO3)3·6.5H2O. At 140–220 °C, Sc4O5(NO3)3 is formed.

Scandium nitrate has been found to form clusters when in an aqueous solution which can affect its behavior and properties in various ways. Small Angle neutron scattering has been used in experiments to show the clusters can contain as many as 10 scandium ions. This number depends on the concentration of the original scandium nitrate in the solution.

Applications
Scandium nitrate has been found to be a successful catalyst in chemical reactions such as Beckmann rearrangement of ketoximes to amides and the isomerization of allylic alcohols to aldehydes. The catalytic success of scandium nitrate can be increased by modifying its structure in ways such as adding a co catalyst. Scandium nitrate is also the precursor for the synthesis of other scandium based compounds such as scandium oxide or scandium hydroxide. Scandium nitrate has also been investigated for its potential in luminescent materials due to its ability to strongly emit in the blue region of the spectrum.