非线性活性材料:可控制相位匹配性的示例
Hongcheng Lu1, Romain Gautier, Martin D Donakowski
1State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University, 127 Youyixilu Road, Xi'an 710072, China.
Journal of the American Chemical Society
|July 20, 2013
概括
发现相匹配的非线性光学 (NLO) 晶体是关键. 这项研究显示了晶体结构,而不仅仅是效率,确定了NLO材料是否可相匹配 (PM) 的实际应用.
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.
- 光学是什么?光学是什么?
背景情况:
- 非线性光学 (NLO) 晶体对于像第二和生成 (SHG) 这样的应用至关重要.
- 为了实际使用,NLO晶体必须非中心对称 (NCS) 和相匹配 (PM).
- 之前的研究重点是创建NCS化合物和提高SHG效率,经常忽视相匹配性.
研究的目的:
- 调查NCS混合材料中相匹配的起源.
- 合成和比较两个化学上相似的NCS化合物,具有不同的相匹配性.
- 确定分子排列在实现相匹配性中的作用.
主要方法:
- 合成了两个新的混合化合物:[Hdpa]2NbOF5·2H2O和HdpaNbOF4.
- 结晶学分析以确认NCS结构的两个化合物.
- 合成材料的相匹配性 (PM与非PM) 的比较.
主要成果:
- 两种合成的化合物[Hdpa]2NbOF5·2H2O和HdpaNbOF4都被证实是NCS.
- 发现化合物 (I) 是非PM,而化学上相似的化合物 (II) 是PM.
- 有机分子 (dpa) 在晶体结构中的排列决定了相匹配性.
结论:
- 在混合NCS晶体中有机成分的精确排列对于实现相匹配性至关重要.
- 这一发现为设计实用,相匹配的NLO材料提供了新的方向.
- 有机晶体学原理对于理解和预测混合NLO系统中的相匹配性至关重要.
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