Hydrogen-adduction to open-shell graphene fragments: spectroscopy, thermochemistry and astrochemistry.
Hydrogen-adduction to open-shell graphene fragments: spectroscopy, thermochemistry and astrochemistry.
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DOI：
10.1039/c6sc03787a
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发表时间：
2017-02-01
期刊：
影响因子：
8.4
通讯作者：
Schmidt TW
中科院分区：
文献类型：
--
作者：
O'Connor GD;Chan B;Sanelli JA;Cergol KM;Dryza V;Payne RJ;Bieske EJ;Radom L;Schmidt TW
用激光对h -内合的石墨烯碎片进行了研究，揭示了激发态键解离能和电离能。我们应用最先进的实验和量子化学方法的结合来阐明氢内合到一个模型开壳石墨烯片段的电子和化学能量学。能量最低的加合物1H-phenalene的键离解能为258.1 kJ mol-1，而其他同分异构体的键离解能降低或在某些情况下为负，亚稳物质通过沿高对称离解坐标出现的锥形相交而结合。利用激光光谱与质谱联用技术记录了h -苯及其自由基阳离子的气相激发谱。观察到两种物质的几个电子激发态，从而确定激发态键解离能。1h -吩烯的电离能为7.449(17)eV，与高能级W1X-2计算结果一致。
H-Adducted graphene fragments are interrogated with lasers, revealing excited state bond dissociation energies and ionization energies. We apply a combination of state-of-the-art experimental and quantum-chemical methods to elucidate the electronic and chemical energetics of hydrogen adduction to a model open-shell graphene fragment. The lowest-energy adduct, 1H-phenalene, is determined to have a bond dissociation energy of 258.1 kJ mol–1, while other isomers exhibit reduced or in some cases negative bond dissociation energies, the metastable species being bound by the emergence of a conical intersection along the high-symmetry dissociation coordinate. The gas-phase excitation spectrum of 1H-phenalene and its radical cation are recorded using laser spectroscopy coupled to mass-spectrometry. Several electronically excited states of both species are observed, allowing the determination of the excited-state bond dissociation energy. The ionization energy of 1H-phenalene is determined to be 7.449(17) eV, consistent with high-level W1X-2 calculations.