SOLID SOLUTIONS OF COMPLEX YTTRIUM AND EUROPIUM BORATES Li6R(BO3)3 AND LiR6(BO3)3O5, R = Y, Eu

Abstract X-ray quality crystals of solid solutions of complex borates Li6R(BO3)3 and LiR6(BO3)3O5 (R = Y, Eu) with different europium contents are grown from a Li6R(BO3)3 melt solution with an addition of 20 mol.% of an yttrium–europium oxide mixture. The structural data show that the Y/Eu distribution over independent positions in the LiR6(BO3)3O5 crystal is nonuniform; the difference between Eu occupancies reaches 80% and correlates with the Hirshfeld volumes of these sites calculated for LiR6B3O14.