Photo-luminescence properties of Cu and Ag doped Li2B4O7 single crystals at low temperatures

► Growth of crack free single crystals of Li2B4O7 with codoping of Cu and Ag. ► Ratio of 1A1g→1T2g and 1A1g→1Eg transitions probability from excitation spectra. ► Off-center or lower symmetry position of Cu+ ions in the lattice. ► Study of temperature dependence of photoluminescence properties.