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Updated: Jan 8, 2026
Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
Published on: November 30, 2012
Heterocationic strategy to design a nonlinear optical crystal with a polar anti-perovskite structure
Shuoxing Yang1, Hongping Wu1, Zhanggui Hu1
1State Key Laboratory of Crystal Materials, Tianjin Key Laboratory of Functional Crystal Materials, Department of Functional Crystals, Tianjin University of Technology, Tianjin, China.
Abstract:
The rational design of noncentrosymmetric (NCS) inorganic materials remains a longstanding challenge due to unpredictable solid-state reactions and stringent requirements on symmetry breaking. Although perovskites have been widely used as structural templates for NCS materials, their anti-perovskite counterparts remain unexplored. Here, by incorporating Cs+ and Cd2+ ions into a centrosymmetric Na3Cl[MoO4] template, we introduce a heterocationic strategy tailored for anion-centered anti-perovskites that, modifying the conventional BX6 octahedra, yields the polar molybdate Cs2NaCd2Cl3(MoO4)2. The heterocationic sublattice induces pronounced octahedral distortion, breaks inversion symmetry, and aligns the [MoO4] tetrahedra, resulting in a wide band gap of 4.37 eV, a broad transparency window (0.26-5.42 μm and 6.25-10.46 μm), an SHG coefficient twenty times larger than KH2PO4 (d15 = 9.31 pm/V) and a congruent-melting dynamics, enabling single-crystal growth. This work unveils the potential of heterocationic engineering in anion-centered frameworks demonstrating the design of NCS and polar functional materials with excellent nonlinear optical properties.
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