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负离子光电子谱学证实了 (CO) 5和 (CO) 6各自具有单个基态的预测
Xiaoguang Bao1, David A Hrovat, Weston Thatcher Borden
1Department of Chemistry and the Center for Advanced, Scientific Computing and Modeling, University of North Texas, 1155 Union Circle, #305070, Denton, Texas 76203-5070, USA.
Journal of the American Chemical Society
|March 1, 2013
概括
循环丁-1,2,3,4-四 (CO) 4具有三重基态,而循环-1,2,3,4,5- (CO) 5和循环-1,2,3,4,5,6- (CO) 6具有单个基态. 通过光电子光谱学和计算分析证实了这一点.
科学领域:
- 物理化学 物理化学
- 量子化学 是一个量子化学.
- 频谱学是一种光谱学.
背景情况:
- 据预测,循环butan-1,2,3,4-tetraone (CO) 4由于单独占据的分子轨道,因此具有三重基态.
- 相比之下,理论研究表明 (CO) 5和 (CO) 6.6的单个基本状态.
研究的目的:
- 实验验证 (CO) 4, (CO) 5 和 (CO) 6.6 的基本状态电子配置.
- 为了确定这些化合物的电子亲和度和单元-三元能量差异.
主要方法:
- 通过电喷雾蒸发产生 (CO) 5 ((•-) 和 (CO) 6 ((•-) 基离子.
- 负离子光电子 (NIPE) 光谱检测电子状态.
- 高级计算化学计算 ((RO)CCSD(T) /aug-cc-pVTZ//(U) B3LYP/6-311+G(2df)) 用于能量和振动分析.
主要成果:
- 在 (CO) 5的NIPE频谱中,单电 (CO) 5的电子亲和力为3.830 eV,三电状态的电子亲和力比0.850 eV高.
- 在 (CO) 6 的 NIPE 频谱中,单电 (CO) 6 的电子亲和力为 3.785 eV,三电状态的电子亲和力为 0.915 eV.
- 计算的电子亲和度和单元-三元能量差距与实验NIPE数据密切匹配,支持观察到的基本状态.
结论:
- 实验和计算证据证实了 (CO) 4.4.的三重基本状态.
- (CO) 5和 (CO) 6呈现单个基本状态,与理论预测一致.
- 与弗兰克-康登因子计算相结合的NIPE光谱学提供了一种可靠的方法来确定基态电子配置和能量.
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