在纳米粉尘等离子体成分的热化学上有很大的热效应
Prasenjit Seal1, Donald G Truhlar
1Department of Chemistry, Supercomputing Institute, and Chemical Theory Center, University of Minnesota , Minneapolis, Minnesota 55455-0431, United States.
Journal of the American Chemical Society
|January 18, 2014
概括
多结构效应和扭曲不协调性对于准确确定化集群的热力学特性至关重要. 这些发现强调了考虑多个分子结构对于精确的热化学计算的重要性.
科学领域:
- 物理化学 物理化学
- 计算化学计算化学
- 材料科学 材料科学 材料科学
背景情况:
- 精确的热力学特性对于设计等离子体介导沉积的控制策略至关重要.
- 化集群在等离子体和热驱动系统中都至关重要.
- 传统的方法往往忽视了多个分子结构的重要性.
研究的目的:
- 为了研究多结构效应和扭转不协调性对化集群热力学的影响.
- 为了比较一个新的多结构方法与现有的方法,如组添加性.
- 为了提供准确的热力学数据的silanes,silyl激素,和silenes.
主要方法:
- 采用多结构 (MS) 和性方法与密度函数理论 (DFT) 相结合.
- 计算分区函数以估计吉布斯自由能量,,和热容量.
- 使用了多结构准和近似 (MS-QH) 并包括扭力潜力不和性 (MS-T).
主要成果:
- 在化系统中,发现多结构效应非常显著.
- 计算的热力学量与组添加性 (GA) 结果有很大差异.
- 对热化学的效应很大,主要是由多结构贡献驱动的.
结论:
- 多结构无协调性方法为化集群提供了更准确的热力学性质的确定.
- 多结构效应至关重要,应纳入用于精确的热化学预测.
- 预计多重结构的热影响会影响其他分子系统和核化动力学.
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