Reaction between barium and nitrogen in liquid sodium: solubility studies

Abstract

Nitrogen in increasing amounts has been added to separate solutions of barium in sodium of constant composition (ca. 4.40 mol % Ba) at 300 °C. After rendering each mixture homogeneous using an electromagnetic pump, filtration, and nitrogen analysis, all the N₂ added has been found in solution up to a solution composition approximating to Ba₄N (i.e. 1.1 mol % N) beyond which the quantity of dissolved N₂ decreases progressively due to precipitation of the nitride Ba₂N. The solubilization is interpreted in terms of strong preferential solvation of the nitride ion by barium cations.