Hydrothermal growth of LiLuF4 crystals and new lithium lutetium fluorides LiKLuF5 and LiNaLu2F8

► C-centered monoclinic LiKLuF5 has been synthesized hydrothermally. ► Spectroscopy of doped LiKLnF5 complexes is shown in this paper. ► A new C-centered orthorhombic crystal, LiNaLu2F8 was also prepared. ► These new materials were synthesized as side products of making LiLuF4.