PbCdF(SeO₃)(NO₃): A Nonlinear Optical Material Produced by Synergistic Effect of Four Functional Units

A new nonlinear optical material, the first fluoride selenite nitrate PbCdF­(SeO3)­(NO3), was successfully synthesized by traditional solid state reactions. This compound crystallizes in the polar space group of Pca21, and its structure features a novel 2D layered structure consisting of 1D lead nitrate chains and 2D cadmium selenite layers. PbCdF­(SeO3)­(NO3) exhibits a phase-matchable SHG efficiency of about 2.6 times that of KDP and a wide band gap of 4.42 eV. Its laser damage threshold was measured to be 135.6 MW/cm2, which is comparative to that of the reported Li7­(TeO3)3F with a short ultraviolet cutoff edge. Theoretical calculation confirmed that the synergistic effects of all the four functional units make PbCdF­(SeO3)­(NO3) a remarkable SHG material