Atahan-Evrenk Sule
TOBB University of Economics and Technology, Faculty of Medicine Sogutozu Cad No. 43 Sogutozu Ankara Turkey
RSC Adv. 2018 Dec 4;8(70):40330-40337. doi: 10.1039/c8ra07866a. eCollection 2018 Nov 28.
Intramolecular reorganization energy (RE), which quantifies the electron-phonon coupling strength, is an important charge transport parameter for the theoretical characterization of molecular organic semiconductors (OSCs). On a small scale, the accurate calculation of the RE is trivial; however, for large-scale screening, faster approaches are desirable. We investigate the structure-property relations and present a quantitative structure-property relationship study to facilitate the computation of RE from molecular structure. To this end, we generated a compound set of 171, which was derived from known p-type OSCs built from moieties such as acenes, thiophenes, and pentalenes. We show that simple structural descriptors such as the number of atoms, rings or rotatable bonds only weakly correlate with the RE. On the other hand, we show that regression models based on a more comprehensive representation of the molecules such as SMILES-based molecular signatures and geometry-based molecular transforms can predict the RE with a coefficient of determination of 0.7 and a mean absolute error of 40 meV in the library, in which the RE ranges from 76 to 480 meV. Our analysis indicates that a more extensive compound set for training is necessary for more predictive models.
分子内重组能（RE）用于量化电子 - 声子耦合强度，是用于分子有机半导体（OSC）理论表征的重要电荷传输参数。在小尺度上，RE的精确计算很简单；然而，对于大规模筛选，需要更快的方法。我们研究了结构 - 性质关系，并进行了定量结构 - 性质关系研究，以促进从分子结构计算RE。为此，我们生成了一个包含171种化合物的集合，该集合源自由诸如并苯、噻吩和戊搭烯等部分构建的已知p型OSC。我们表明，诸如原子数、环数或可旋转键数等简单结构描述符与RE的相关性较弱。另一方面，我们表明基于分子更全面表示（如基于SMILES的分子特征和基于几何的分子变换）的回归模型可以在该库中预测RE，决定系数为0.7，平均绝对误差为40 meV，其中RE范围为76至480 meV。我们的分析表明，对于更具预测性的模型，需要更广泛的训练化合物集。
