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通过优化激光重复率提高尿素结晶的可预测性

Leon Geiger¹, Ian Howard¹, Neil MacKinnon¹

¹Institute of Microstructure Technology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen 76344, Germany.

Crystal growth & design

|May 6, 2024

概括

优化脉冲重复率是可预测有机分子激光诱导结晶的关键. 发现500 Hz至1 kHz的最佳范围显著提高了结晶成功率.

科学领域:

* 物理化学物理化学
* 材料科学材料科学
* 激光物理激光物理

背景情况:

*激光诱导结晶为结晶有机分子提供了一种新的方法.
*精确控制实验参数对于可预测结果至关重要.
*脉冲重复率对结晶诱导时间的影响尚不清楚.

研究的目的:

* 研究激光脉冲重复率对激光诱导结晶的诱导时间的影响.
* 为了确定一个最佳的脉冲重复率,以实现高效的结晶.
* 了解影响不同重复率的结晶效率的潜在机制.

主要方法:

* 用近红外 (1030 nm) 激光脉冲 (5 ps 持续时间, ~340 μJ 能量) 辐射超和尿素溶液.
*系统地改变脉冲重复率从10 Hz到20,000 Hz.
*测量结晶启动的时间延迟 (诱导时间),并计算成功结晶事件的概率.

主要成果:

*在500Hz和1kHz之间确定了最佳的脉冲重复率,产生2-5秒的中位诱导时间.
*成功结晶的平均概率在最佳范围 (5 × 10-2%) 中最高.
*更高的重复率 (5-20 kHz) 显著降低了结晶概率 (3 × 10−3%),可能是由于热化气泡相互作用.

结论:

*脉冲重复率是控制激光诱导结晶的关键参数.
*优化的脉冲重复率提高了结晶有机分子的可预测性和效率.
* 了解脉冲相互作用,例如热化气泡,对于流程优化至关重要.

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