Quantum Chemical Research on Carbon Clusters and Other Projects

碳团簇量子化学研究等项目

• 批准号: 8703285
• 负责人: Richard Stanton
• 金额: $ 3.39万
• 依托单位: Canisius College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-06-01 至 1989-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8703285&HistoricalAwards=false
• 关键词: Quantum; Chemical; Research; Carbon; Clusters

Laser vaporization studies have demonstrated the stability of a family of even-numbered carbon clusters ranging in size from about 38 to 150 atoms. It has been suggested that C60, the most prominent member of this family, has a hollow structure similar in shape and structure to a soccerball. MNDO calculations have confirmed the vibrational stability of this structure and have shown it to be energetically stable relative to silmilarly sized graphite chips and other competing structures. Additional MNDO calculations have indicated stability for spheroidal C40, C50, and C70 clusters. This project involves a systematic search for stable spheroidal structures for the remaining even-numbered carbon clusters. The MNDO caculations will be preceded by graph theoretical analysis to see which ring combinations are topologically possible, and by Huckel calculations to see which are likely to have closed shell electronic structures. Hollow carbon clusters of the type described above may play a role in the formation of soot and the transportation of other molecules in interstellar space, and may lead to novel lubricants. A fundamental understanding of these structures is needed and is addressed by this project. Moreover, the project will also benefit the infrastructure of U.S. science by providing exposure of talented undergraduates to advanced computing techniques and equipment.

激光蒸发研究表明，一系列大小从38到150个原子的偶数碳原子团是稳定的。有人认为C60是这个家族中最重要的成员，在形状和结构上类似于足球的中空结构。MNDO计算证实了这种结构的振动稳定性，并表明它相对于微米大小的石墨片和其他竞争结构在能量上是稳定的。另外的MNDO计算表明，球形C40、C50和C70团簇是稳定的。这个项目包括系统地为剩余的偶数碳原子团寻找稳定的球状结构。在MNDO计算之前，将通过图论分析来确定哪些环组合在拓扑上是可能的，并通过休克尔计算来确定哪些环可能具有闭合壳层电子结构。上述类型的中空碳团簇可能在碳烟的形成和星际空间中其他分子的运输中发挥作用，并可能导致新型润滑剂的出现。需要对这些结构有一个基本的了解，并由本项目加以解决。此外，该项目还将为有才华的本科生提供接触先进计算技术和设备的机会，从而使美国科学基础设施受益。