Investigation on the Li, Ba//BO2, F ternary reciprocal system and growth of bulk β-BaB2O4 crystals

•The Li, Ba//BO2, F system is promising for the growth of β-BaB2O4 crystals.•The bulk β-BaB2O4 crystals in the BaB2O4–LiF system were grown.•The boules of β-BaB2O4 were grown in BaB2O4–LiBaF3 and BaB2O4–LiBaBO3 systems.

Methods of spontaneous crystallization on a platinum loop, modified VPA method, solid phase synthesis, X-ray powder diffraction analysis and chemical analyses were used to study phase formation in the Li, Ba//BO2, F ternary reciprocal system and the base of the BaO–B2O3–Li2O prism of quaternary reciprocal system Ba, B, Li//O, F. In these systems the fields of primary crystallization of β-BaB2O4 were determined and a promising solvent for crystal growth was found. A series of experiments were carried out on the growth of bulk barium borate crystals in the system BaB2O4–LiF.