富勒烯C70内部的分子:量子动力学,能量学,最大占用率,与C60进行比较
Francesco Sebastianelli1, Minzhong Xu, Zlatko Bacić
1Department of Chemistry, New York University, New York, New York 10003, USA.
Journal of the American Chemical Society
|June 30, 2010
概括
这项研究表明,内分体富勒烯复合体最多可以稳定C70中的两个 (H) 分子和C60中的一个 (H) 分子. 量子力学计算突出了转换-旋转零点能量在确定稳定性的关键作用.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 量子力学就是量子力学.
背景情况:
- 带有封装分子 (H(2) 的内分体烯复合物最近因其独特的特性而引起了人们的兴趣.
- 了解封闭的H2的动态和能量行为对于预测复杂稳定性至关重要.
研究的目的:
- 从理论上研究C70) 和C60) 富勒烯中的对 (p-H) 分子的合转换和旋转动力学.
- 确定这些内分体复合体的能量稳定性和最大H2含量.
主要方法:
- 使用扩散蒙特卡罗 (DMC) 计算进行严格的理论研究.
- 计算的重点是地面状态属性,能量和转换旋转 (T-R) 零点能量 (ZPE).
- 对封装的p-H(2) 分子的分子间潜在能量表面 (PES) 的分析.
主要成果:
- 预测能量稳定的复合体在C70中最多有两个p-H2和在C60中一个p-H2 .
- 第三个p-H ((2) 在C ((70) 中,第二个p-H ((2) 在C ((60) 中,导致了显著的能量不稳定.
- 转换-旋转零点能量 (T-R ZPE) 是相当大的,对整体的能量和稳定性预测产生重大影响.
结论:
- 在C70中最多可以稳定两个H2分子,在C60中只能稳定一个,这与最近的实验发现相一致.
- 准确计算T-R ZPEs对于可靠的理论预测内分体富勒烯复合体稳定性至关重要.
- 这些发现为纳米封闭分子的量子力学行为提供了关键的见解.
相关概念视频
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