中国科学院福建物质结构研究所罗军华研究团队揭示了极性[NH（CH₂SO₃）₂]^2-二聚体使第一个具有非线性光学性质和宽紫外透明度的亚氨基二甲磺酸酯成为可能。该项研究成果发表在2025年3月25日出版的《中国化学》上。

在这项工作中，该研究组引入了极性[NH（CH₂SO₃）₂]^2-二聚体作为新型非π共轭FBU，合成了第一个NLO亚氨基甲磺酸盐晶体Cs₂NH(CH₂SO₃)₂·H₂O。实验结果表明，该晶体具有0.8倍KDP的二次谐波产生（SHG）响应，适度的双折射为0.044@550nm，较宽的紫外透明度(<在266nm的关键紫外波长上实现相位匹配的SHG。第一性原理计算证实极性[NH(CH₂SO₃)₂]^2-二聚体有助于Cs₂NH(CH₂SO₃)₂·H₂O的光学性质。这项工作突出了一个优秀的紫外NLO活性FBU，用于探索高性能紫外NLO晶体。

据了解，非π共轭基团由于具有广泛的透明度，近年来已成为紫外非线性光学（NLO）晶体的优良基本结构单元（FBUs）。然而，它们普遍较高的晶体对称性往往导致有限的光学各向异性，使得很少有合成晶体在紫外波长范围内相位匹配。

附：英文原文

Title: Polar [NH(CH2SO3)2]2− Dimers Enable the First Promising Iminodimethanesulfonate with Nonlinear Optical Properties and Wide UV Transparency

Author: Yipeng Song, Yuexin Zhang, Yanqiang Li, Zhiyong Bai, Weiqi Huang, Kunpeng Wang, Sangen Zhao, Junhua Luo

Issue&Volume: 2025-03-25

Abstract: Non-π-conjugated groups have recently emerged as excellent fundamental building blocks (FBUs) for UV nonlinear optical (NLO) crystals, due to their ability to achieve wide transparency. However, their generally high crystallographic symmetry often results in limited optical anisotropy, making few resultant crystals phase-matchable in the UV wavelength range. In this work, we introduce the polar [NH(CH2SO3)2]2 dimer as a novel non-π-conjugated FBU, and synthesize the first NLO iminodimethanesulfonate crystal, namely Cs2NH(CH2SO3)2·H2O. Experimental results demonstrate that this crystal exhibits second-harmonic generation (SHG) responses with 0.8 times of KDP, moderate birefringence of 0.044@550 nm, and broad UV transparency (<200 nm), enabling phase-matchable SHG at the key UV wavelength of 266 nm. First-principles calculations confirm that polar [NH(CH2SO3)2]2 dimers contribute to the optical properties of Cs2NH(CH2SO3)2·H2O. This work highlights an excellent UV NLO-active FBU for exploring high-performance UV NLO crystals.

DOI: 10.1002/cjoc.70006

Source: https://onlinelibrary.wiley.com/doi/full/10.1002/cjoc.70006