解释基烯中的分子晶体障碍,Pb(C5H5) 2:从理论中获得的洞察力
Carole A Morrison1, Dominic S Wright, Richard A Layfield
1Department of Chemistry, University of Edinburgh, The Kings Buildings, West Mains Road, Edinburgh, EH9 3JJ, United Kingdom. c.morrison@ed.ac.uk
Journal of the American Chemical Society
|June 6, 2002
概括
平面波密度函数理论揭示,在古时代,分层的环甲基环比被遮蔽的环更稳定. 这种量子力学方法首次确定了晶体学占用因子.
科学领域:
- 固态化学 固态化学
- 量子化学是一种量子化学.
- 晶体学 晶体学是指结晶学.
背景情况:
- 乙烯 (Pb(C5H5) 2) 呈现出分子晶体结构障碍.
- 了解这种障碍对于预测材料性质至关重要.
研究的目的:
- 为了解释plumbocene. orthorhombic zigzag阶段观察到的障碍.
- 为了确定循环二烯环的分层和遮蔽包装安排之间的能量偏好.
主要方法:
- 平面波密度函数理论 (DFT) 的应用.
- 计算不同的包装安排的格子能量.
- 使用量子力学确定晶体占用因子.
主要成果:
- 一个均分层的C5H5环排列在能量上比一个均覆盖的排列更受欢迎,每单元细胞有2.8kJ mol-1.
- 能量差异归因于代链之间的分子间相互作用的变化.
- 量子力学计算成功确定了晶体学占用因子.
结论:
- 由于更强的分子间相互作用,plumbocene的分层包装更稳定.
- 这项研究展示了一种新的量子力学方法,用于确定无序系统中的晶体学占用因子.
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