紫外线光电子光谱 BN 内醇:实验和计算电子结构分析分析
Anna Chrostowska1, Senmiao Xu, Audrey Mazière
1Department of Chemistry, Boston College , Chestnut Hill, Massachusetts 02467, United States.
Journal of the American Chemical Society
|August 5, 2014
概括
这项研究使用紫外线光电谱学和计算化学分析- (BN) 类同类物. 与单环系统相比,双环系统中的电子结构和反应能力受到BN同质的影响不同.
科学领域:
- 物理化学 物理化学
- 计算化学计算化学
- 频谱学是一种光谱学.
背景情况:
- 印衍生物在药物化学和材料科学中至关重要.
- 了解醇的电子结构对于预测其性质至关重要.
- - (BN) 同质化提供了一个修改芳香系统的途径.
研究的目的:
- 为了研究两种内的BN异的电子结构.
- 通过实验和计算方法,将它们的特性与自然的醇进行比较.
- 评估BN/CC同质性对内核的影响.
主要方法:
- 气相紫外线光电子光谱学 (UV-PES) 使用热电辐射.
- 密度函数理论 (DFT) 对电子结构的计算.
- 对电离能量的分析,双极时刻,紫外线吸收和电友芳香替代.
主要成果:
- 第一个电离能:醇 (7.9 eV),外部的BN醇I (7.9 eV),化的BN醇II (8.05 eV).
- 双极矩: 内极 (2.177 D) > 合的 BN 内极 II (1.512 D) > 外部的 BN 内极 I (0.543 D).
- 紫外线的吸收 (λmax):化的BN 道II (292 nm) >外部BN道I (282 nm) >道 (270 nm).
- 反应性趋势:化BN 醇II > 醇 > 外部BN醇I.
- 引入BN降低了6π电子系统中的芳香度.
结论:
- BN同质化显著改变了内醇核的电子结构和反应性.
- 观察到的趋势与单环系统的趋势有所不同,因此需要对特定系统进行评估.
- BN/CC异构效应不是普遍可转移的,需要进行个别评估.
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