Defect-induced wetting on BaF2(111) and CaF2(111) at ambient conditions

► Wetting of cleaved (111) surfaces of BaF2 and CaF2 at ambient conditions results from the presence of defects and steps. ► Dipole-oriented water layers are formed on BaF2(111) due to near lattice matching with hexagonal ice. ► CaF2(111) does not promote the formation of water layers due to lattice mismatch.