Large Nonlinear Optical Effect in Tungsten Bronze Structures via Li/Na Cross-Substitutions Shihang Chu, Kun Lin, Tao Yang, Chengyi Yu, Yili Cao, Yujuan Zhang, Yujiao Sun, Zerui Li, Xingxing Jiang, Zheshuai Lin, Qiang Li, Jun Chen, Kenichi Kato, Hui Wu, Qingzhen Huang and Xianran Xing Abstract By a simple cross-substitution of A-site Li/Na in tetragonal tungsten bronze (TTB) structures, we successfully synthesized a new niobate compound, Pb2.15(Li0.25Na0.75)0.7Nb5O15, with a (2√2aTTB, √2bTTB,...