A computational exploration of the crystal energy and charge-carrier mobility landscapes of the chiral [6]helicene molecule.
A computational exploration of the crystal energy and charge-carrier mobility landscapes of the chiral [6]helicene molecule.
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对手性[6]螺烯分子的晶体能量和电荷载流子迁移率态势的计算探究
DOI：
10.1039/c7nr08890f
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发表时间：
2018-01
期刊：
影响因子：
6.7
通讯作者：
Beth Rice;Luc M. LeBlanc;A. Otero-de-la-Roza;M. Fuchter;E. Johnson;J. Nelson;K. Jelfs
中科院分区：
文献类型：
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作者：
Beth Rice;Luc M. LeBlanc;A. Otero-de-la-Roza;M. Fuchter;E. Johnson;J. Nelson;K. Jelfs
有机半导体器件中给定的π-共轭有机分子的电势高度依赖于分子堆积，因为它强烈影响材料的电荷载流子迁移率。这种固态堆积对它们分子间相互作用的细微差异很敏感，并且很难预测。有机分子的手性为直观的堆积预测增加了额外的复杂性。在这里，我们使用晶体结构预测来探索潜在手性有机半导体的晶格能景观，[6]螺烯。我们重现实验观察到的对映体纯的晶体结构，并解释实验观察到的racket结构的情况下。通过探索空穴和电子迁移率如何在[6]螺旋烯的能量-结构-功能景观中变化，我们发现能量有利且经常发生的填充基序对电子迁移率特别有希望，最高计算迁移率为2.9 cm 2 V-1 s-1（假设重组能为0.46 eV）。我们还计算了相对较高的空穴迁移率在某些结构中，与最高的计算迁移率为2.0厘米2 V-1 s-1的helicenes的链包装在一个人字形的方式。无论是积极有利的，也不是高电荷载流子迁移率包装图案是直观明显的，这表明了我们的方法计算探索有机半导体的能量-结构-功能景观的实用性。我们的工作展示了一条使用计算模拟来帮助设计有机电子新分子的路线，通过先验预测它们可能的固态形式和性质。
The potential of a given π-conjugated organic molecule in an organic semiconductor device is highly dependent on molecular packing, as it strongly influences the charge-carrier mobility of the material. Such solid-state packing is sensitive to subtle differences in their intermolecular interactions and is challenging to predict. Chirality of the organic molecule adds an additional element of complexity to intuitive packing prediction. Here we use crystal structure prediction to explore the lattice-energy landscape of a potential chiral organic semiconductor, [6]helicene. We reproduce the experimentally observed enantiopure crystal structure and explain the absence of an experimentally observed racemate structure. By exploring how the hole and electron-mobility varies across the energy-structure-function landscape for [6]helicene, we find that an energetically favourable and frequently occurring packing motif is particularly promising for electron-mobility, with a highest calculated mobility of 2.9 cm2 V-1 s-1 (assuming a reorganization energy of 0.46 eV). We also calculate relatively high hole-mobility in some structures, with a highest calculated mobility of 2.0 cm2 V-1 s-1 found for chains of helicenes packed in a herringbone fashion. Neither the energetically favourable nor high charge-carrier mobility packing motifs are intuitively obvious, and this demonstrates the utility of our approach to computationally explore the energy-structure-function landscape for organic semiconductors. Our work demonstrates a route for the use of computational simulations to aid in the design of new molecules for organic electronics, through the a priori prediction of their likely solid-state form and properties.