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Updated: Sep 10, 2026
Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)
Published on: January 17, 2020
HSAB-Guided Design of Chiral Osmium Halides With Both Efficient Nonlinear Optical Properties and High Stability
Wenting Liu1, Xin Zeng1,2, Wenkai Zhao1
1Frontiers Science Center for New Organic Matter, Tianjin Key Lab for Rare Earth Materials and Applications, National Key Laboratory of Semiconductor Laser, Academy for Advanced Interdisciplinary Studies, Renewable Energy Conversion and Storage Center (RECAST), School of Materials Science and Engineering, Nankai University, Tianjin, China.
Abstract:
Chiral hybrid organic-inorganic metal halides (HOIMHs) hold great promise for nonlinear optical (NLO) applications. However, their practical applications are severely hindered by the poor environmental stability and photostability. Herein, guided by the hard and soft acids and bases (HSAB) theory, we quantitatively calculated and compared the chemical hardness of all elements in the periodic table based on density functional theory, and found osmium (Os) exhibits the highest chemical hardness among Group VIII transition metals. Thus, we synthesized the chiral osmium-based HOIMHs, (R/S-3BrMBA)2OsCl6 (R/S-Os), and systematically investigated their NLO properties and stability. As expected, the obtained chiral osmium halides remain stable after two months of exposure to air, and the second-harmonic generation (SHG) intensity remains almost unchanged after the same period, confirming their outstanding long-term stability. The efficient SHG responses with effective second-order nonlinear susceptibility (χeff) of 6.4 pm/V and strong SHG circular dichroism (SHG-CD) with anisotropy factor (|gSHG-CD|) of 0.33 are also observed. Our work provides valuable HSAB-guided screening strategy for predicting and designing the highly stable NLO materials.
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