局部反应描述器如何塑造与化学反应相关的潜在能量表面? 瓦伦斯债券迁移的前景
Thijs Stuyver1,2, Frank De Proft2, Paul Geerlings2
1Institute of Chemistry, The Hebrew University, Jerusalem 91904, Israel.
Journal of the American Chemical Society
|May 6, 2020
概括
密度函数理论 (DFT) 的局部反应性描述器是反应物的非局部化间接测量,解释化学反应性和区域选择性. 这种价值键 (VB) 分析揭示了这些描述符可能会失效的情况,特别是在双重反应的情况下.
科学领域:
- * 量子化学
- * 理论化学
- * 化学反应理论
背景情况:
- 在概念密度函数理论 (DFT) 中,局部反应性描述器,如福基函数和局部自旋密度分布,通常被使用.
- * 这些描述符旨在预测化学反应中的反应性趋势和区域选择性偏好.
- 需要更深入地了解这些局部描述和全球潜在能量表面 (PES) 之间的关系.
研究的目的:
- * 调查局部反应性描述器如何影响化学反应的潜在能量表面 (PES).
- *对基于DFT的局部反应性描述器和价值键 (VB) 理论之间的联系进行定性分析.
- * 为了解局部反应性描述器的预测能力和局限性提供一个框架.
主要方法:
- * 定性价值键 (VB) 分析
- 基于常见密度函数理论 (DFT) 的局部反应性描述器的检查.
- 在VB框架内分析移位和共振稳定.
主要成果:
- * 基于DFT的局部反应性描述器被证明是VB理论中反应物移位和共振稳定的间接指标.
- * VB框架自然解释了地方描述因素对全球 PES 的影响.
- * 确定了局部描述器可能无法预测反应性趋势的条件,例如在雄心勃勃的反应性.
结论:
- * 局部反应性描述器可以通过VB理论的移位和共振稳定概念来解释.
- 这项研究提供了统一VB理论和概念DFT的第一步.
- 对于准确的反应性预测来说,了解局部描述符与移位之间的联系至关重要.
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