X-Ray analysis of two phases in the barium borate, sodium barium borate and sodium borate ternary phase diagram

Abstract

Aspects of the ternary phase diagram of barium borate (BaB₂O₄), sodium barium borate (Na₂BaB₂O₅) and sodium borate (Na₂B₂O₄) have been investigated. The lattice parameters of sodium barium borate (NBBO) were determined and a probable unit cell was calculated. An unknown high-temperature phase was also found. NBBO has a monoclinic unit cell with a= 9.576(0.01)Å, b= 5.570(0.003)Å, c= 6.183(0.003)Å and β= 98.92(0.04)° and a calculated density of 3.0 g cm^–3. The high-temperature phase is also probably monoclinic with lattice parameters of a= 11.91 Å, b= 14.14 Å, c= 6.39 Å and β= 99.39°.