在化纳米酸盐中寻找性:DFT和TD-DFT调查
Kamil B Stelmach1,2, Catherine A Dukes2, Robin T Garrod1,3
1Department of Chemistry, University of Virginia, Charlottesville, Virginia 20904, United States.
The journal of physical chemistry. A
|April 30, 2024
概括
这项研究使用计算化学来探索星际酸盐颗粒如何与相互作用. 结果显示,这些酸盐可能会变为奇拉性,这可能解释了石中奇拉性的起源.
科学领域:
- 天体化学和计算纳米科学
- 研究星际酸盐粒的形成和特性及其与物种的相互作用.
背景情况:
- 星际介质 (ISM) 中性酸盐颗粒的形成尚未得到充分理解.
- 酸盐-相互作用至关重要,因为是ISM中最丰富的元素,并在分子形成中发挥作用.
- 酸盐表面在ISM中催化分子 (H2) 的形成.
研究的目的:
- 在天体物理相关条件下以计算方式研究潜在的纳米结构及其特性.
- 探索化酸盐表面在模板化石中发现生物分子的反体过剩中的作用.
- 确定纳米颗粒对圆极化光 (CPL) 的不对称吸收是否可以打破对称性并诱导性.
主要方法:
- 使用密度函数理论 (DFT) 和时间依赖的DFT (TD-DFT) 计算.
- 研究了26个纳米酸盐结构,具有不同程度的化 (无,中性H,质子H,分子H2).
- 使用HSE06/aug-cc-pVQZ用于DFT和CAM-B3LYP/cc-pVQZ和TD-DFT的 ωB97X-D3/cc-pVQZ计算的属性和循环二元化谱.
主要成果:
- 所有26个纳米酸盐结构都表现出0.628.3微米范围的吸收带,可以通过詹姆斯·韦伯太空望远镜检测到.
- 在与UV-CPL相互作用时,在八种合性恩斯酸二次体中观察到一个小的选效应,预测的g值高达0.007.7.
- 这表明,无机酸盐材料可以通过UV-CPL变得异构偏差.
结论:
- 这项研究表明,纳米酸盐颗粒可以吸收循环偏光,导致微小程度的诱导性性.
- 这种机制为无机物质在太空中变得富含的潜在途径提供了途径.
- 这种性酸盐颗粒可以作为模板,驱动在石中发现的有机分子中观察到的性增强.
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