巨型SHG在分子晶体中通过压力驱动的形态异构化切换
Zheng Tang1, Haosen Kang1, Song Gao1
1State Key Laboratory of Advanced Waterproof Materials, School of Materials Science and Engineering, Peking University, Beijing, 100871, China.
Small (Weinheim an der Bergstrasse, Germany)
|November 28, 2025
概括
研究人员在晶体中发现了压力诱导的分子变化,导致光电子设备的第二和生成 (SHG) 显著提升. 这一发现为设计先进的光切换材料提供了新的途径.
科学领域:
- 材料科学 材料科学 材料科学
- 晶体学 晶体学是指结晶学.
- 非线性光学是非线性光学.
背景情况:
- 第二和生成 (SHG) 切换材料对于光电子非常重要.
- 目前的设计通常依赖于"阴离子群理论"和外部刺激引发的结构变化.
- 对于SHG切换的晶体固体中压力诱导的 conformational isomerization 很少得到报道.
研究的目的:
- 为了研究基于皇冠以太的分子晶体中的压力驱动的 conformational isomerization.
- 探索压力诱导的SHG增强背后的机制.
- 开发用于压力响应SHG开关材料的新策略.
主要方法:
- [APIm·18-crown-6][TFSI]·H2O晶体的合成和表征.
- 高压X射线衍射研究.
- 非线性光学 (NLO) 测量以评估SHG信号变化.
主要成果:
- 在0.4 GPa时,观察到SHG信号的巨大增强206倍.
- 这种增强归因于TFSI离子的trans-to-cis形态过渡和动态乱抑制.
- 过渡导致单晶内部的混合相共存,原因是 cis 适配体激活了禁止的衍射平面.
结论:
- 压力驱动的 conformational isomerization 可以大大提高分子晶体中的 SHG 信号.
- 不完整的相位过渡可以诱导显著的NLO属性变化.
- 这项工作为响应压力的高性能光电子材料提供了一个新的设计策略.
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