The understanding of crystal formation in thin films and the precise knowledge of the relation between structure and surface diffusion are two important requirements for the efficient (nano)fabrication of organic electronic devices. Here a computational approach for simulating vapor-phase deposition is employed to obtain and investigate three types of crystalline thin films on graphite. All systems, namely pentacene, perfluoropentacene, and their 1:1 blend, which forms an alternate cocrystal, are constituted by recumbent molecules in accordance with experimental findings. The contributions of intermolecular interactions and of molecular rearrangements occurring during the deposition are analyzed to rationalize the final morphologies. Then, the generated structures are employed to evaluate the energy barriers that prevent molecular diffusion at terraces and step-edges, and to study the reorganization of the films upon high-temperature annealing. The broad agreement with experimental observations and the possibility of evaluating the potential energy surface at the molecular detail render the proposed approach a promising tool to make predictions for other systems.

中文翻译：

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有机半导体薄膜中的共晶生长：模拟并五苯、全氟并五苯及其沉积在石墨上的 1:1 混合物

对薄膜中晶体形成的理解以及对结构与表面扩散之间关系的精确了解是有机电子器件高效（纳米）制造的两个重要要求。这里采用模拟气相沉积的计算方法来获得和研究石墨上的三种类型的晶体薄膜。根据实验结果，所有系统，即并五苯、全氟并五苯及其形成交替共晶的 1:1 混合物，均由卧式分子构成。分析沉积过程中发生的分子间相互作用和分子重排的贡献，以使最终形态合理化。然后，生成的结构用于评估阻止阶梯和阶梯边缘分子扩散的能量势垒，并研究高温退火时薄膜的重组。与实验观察的广泛一致以及评估分子细节势能表面的可能性使得所提出的方法成为对其他系统进行预测的有前途的工具。