Phase relations in the BaO–B2O3–TiO2 system and the crystal structure of BaTi(BO3)2

In this paper, the subsolidus phase relations in the ternary system BaO–B2O3–TiO2 have been investigated. The phase diagram consists of 15 ternary phase regions. There exist 11 binary compounds and two ternary compounds. The ternary compound, BaTi(BO3)2, is isostructural with CaMg(CO3)2. It crystallizes in a rhombohedral system with the space group R-3. The lattice parameters are a=5.0205(2) and c=16.3844(1) Å. Final refinement on the diffraction data converge to Rp=9.09, Rwp=12.24, and Rexp=3.75%.