通过使用总对分布函数G (r) 和密度函数理论,直接确定POSS结构在自组合的离子桥梁式silsesquioxane中
Andressa C Schneid1, João C de Lima2, Fabio F Ferreira3
1Instituto de Química, UFRGS, CP 15003, CEP 91501-970, Porto Alegre, RS, Brazil.
Chemistry, an Asian journal
|August 17, 2024
概括
这项研究通过使用先进的X射线衍射和DFT计算来确定多面寡头性锡尔斯基奥桑 (POSS) 中的原子距离. 研究人员还提出了这些POSS子在离子桥式silsesquioxanes中的六角布置.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 化学 化学 化学
背景情况:
- 多面体寡聚性锡尔斯基奥克桑 (POSS) 是具有独特结构的多功能纳米材料.
- 了解POSS中精确的原子排列对于定制它们的属性至关重要.
- 离子桥式丝二氧化为先进材料应用提供了潜力.
研究的目的:
- 为了阐明离子桥接丝素 (ISSQ) 的短距离和远距离结构特征.
- 为了确定ISSQ.内的POSS的平均原子间距离.
- 提出ISSQ中POSS的长期结构组织.
主要方法:
- 通过桥梁有机原体前体的直接聚凝合成ISSQ的合成.
- 高分辨率同步X射线衍射以获得总对分布函数G (r) 值.
- 密度函数理论 (DFT) 计算用于峰值分配和结构验证.
- 传输电子显微镜 (TEM) 用于检查晶体领域.
主要成果:
- 识别POSS特有的Si-O-Si结构.
- 在ISSQ.中确定T8和T12POSS的平均原子间距离.
- 成功地将DFT与X射线衍射相结合,用于精确的结构分析.
- 建议在ISSQ内对长距离的Si-O-Si子进行六角布置.
结论:
- 该研究提供了第一份关于POSS的原子间距离测定的报告.
- 已经提出了一个新的六角包装POSS子在离子桥 silsesquioxanes中.
- 这些发现提供了对结构组织的见解,这些组织可能会影响材料的特性和应用.
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