Wu, ChaoJiang, XingxingHu, YileiJiang, ChunboWu, TianhuiLin, ZheshuaiHuang, ZhipengHumphrey, MarkZhang, Chi2024-04-081433-7851http://hdl.handle.net/1885/316586The targeted synthesis of deep-ultraviolet (deep-UV) nonlinear optical (NLO) materials, especially those with non-π-conjugated sulfates, has experienced considerable difficulties due to the need to reconcile the oft-competing requirements for deep-UV transparency and strong second-harmonic generation (SHG). We report herein the designed synthesis of the first rare-earth metal-based deep-UV sulfate La(NH4)(SO4)2 by a double-salt strategy involving introduction of complementary cations, together with optical studies that reveal a short-wavelength deep-UV absorption edge (below 190 nm) and the strongest SHG response among deep-UV NLO sulfates (2.4×KDP). Theoretical calculations and crystal structure analysis suggest that the excellent balance between SHG response and deep-UV transparency can be attributed to a synergistic interaction of the hetero-cations La3+ and [NH4]+, which optimize alignment of the [SO4] tetrahedra and highly polarizable [LaO8] polyhedra.application/pdfen-AU© 2021 The authors202110.1002/anie.2021158552022-11-20