碳和纳米结构的碳/前体的结构和热力学
Vassiliki-Alexandra Glezakou1, Jerry A Boatz, Mark S Gordon
1San Diego Supercomputer Centre, University of California San Diego, 9500 Gilman Drive, MC0505, La Jolla, California 92093-0505, USA.
Journal of the American Chemical Society
|May 23, 2002
概括
计算化学揭示了C(36) H(16) 和其杂形式如何经历结构和能量变化. 这项研究探讨了从全碳系统中导致碳纳米管形成的二元化途径.
科学领域:
- 计算化学是一种计算化学.
- 材料科学是一种材料科学.
- 量子化学是一种量子化学.
背景情况:
- 了解碳纳米结构的形成对于先进材料至关重要.
- 富含碳的系统的电子和结构性质会影响它们的反应性.
- 兴奋剂是一种调整碳纳米材料属性的策略.
研究的目的:
- 研究C(36) H(16) 和其Si-doped模拟物C(32) Si(4) H(16) 的结构和能量.
- 探索二元化机制作为碳纳米管和洋类型纳米结构形成的潜在途径.
- 用局部轨道能量分解分析结构变化对电子分布的影响.
主要方法:
- 哈特里-福克水平计算用于结构和能量分析.
- G2 ((MP2,SVP) 方法,其价值为双zeta加极化基础,用于计算形成的标准热量.
- 对同体和同体反应进行分析,以确定热力学稳定性.
- 用于电子分布分析的局部轨道能量分解.
主要成果:
- 详细的结构和能量数据得到了C(36) H(16),C(32) Si(4) H(16),以及较小的碎片.
- 该研究确定了C(36) H(16) 的潜在二元化通道,可以启动纳米结构的形成.
- 电子分布通过局部轨道能量分解与结构配置相关.
结论:
- 计算研究提供了关于碳基和辅助碳系统的稳定性和反应性的见解.
- 分化被提议作为一个关键的初步步骤,在爆炸性形成的碳纳米管从C(36) H(16).
- 这些发现有助于理解碳纳米结构的自我组装机制.
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