Theis Mallory L, Candian Alessandra, Tielens Alexander G G M, Lee Timothy J, Fortenberry Ryan C
Georgia Southern University, Department of Chemistry, Statesboro, GA 30460, USA.
Phys Chem Chem Phys. 2015 Jun 14;17(22):14761-72. doi: 10.1039/c5cp01354b.
The singly deprotonated anion derivatives of nitrogenated polycyclic aromatic hydrocarbons (PANHs) are investigated for their electronically excited state properties. These include single deprotonation of the two unique arrangements of quinoline producing fourteen different isomers. This same procedure is also undertaken for single deprotonation of the three nitrogenation isomers of acridine and the three of pyrenidine. It is shown quantum chemically that the quinoline-class of PANH anion derivatives can only produce a candidate dipole-bound excited state each, a state defined as the interaction of an extra electron with the dipole moment of the corresponding neutral. However, the acridine- and pyrenidine-classes possess valence excited states as well as the possible dipole-bound excited states where the latter is only possible if the dipole moment is sufficiently large to retain the extra electron; the valence excitation is independent of the radical dipolar strength. As a result, the theoretical vertically computed electronic spectra of deprotonated PANH anion derivatives is fairly rich in the 1.5 eV to 2.5 eV range significantly opening the possibilities for these molecules to be applied to longer wavelength studies of visible and near-IR spectroscopy. Lastly, the study of these systems is also enhanced by the inclusion of informed orbital arrangements in a simply constructed basis set that is shown to be more complete and efficient than standard atom-centered functions.
对含氮多环芳烃（PANHs）的单去质子化阴离子衍生物的电子激发态性质进行了研究。这些包括喹啉两种独特排列的单去质子化，产生了十四种不同的异构体。吖啶的三种氮取代异构体和吡啶的三种异构体的单去质子化也采用了相同的程序。量子化学表明，喹啉类PANH阴离子衍生物每种只能产生一个候选偶极束缚激发态，该状态定义为一个额外电子与相应中性分子偶极矩的相互作用。然而，吖啶类和吡啶类既具有价激发态，也具有可能的偶极束缚激发态，后者只有在偶极矩足够大以保留额外电子时才可能存在；价激发与自由基偶极强度无关。结果，去质子化PANH阴离子衍生物的理论垂直计算电子光谱在1.5 eV至2.5 eV范围内相当丰富，这显著拓宽了这些分子应用于可见和近红外光谱更长波长研究的可能性。最后，并在一个简单构建的基组中纳入明智的轨道排列，对这些体系的研究也得到了加强，该基组比标准的以原子为中心的函数更完整、更有效。
