Impact of heteroatoms and chemical functionalisation on crystal structure and carrier mobility of organic semiconductors  

作　　者：S.Hutsch F.Ortmann 

机构地区：[1]Technische Universität München,TUM School of Natural Sciences,Department of Chemistry,Garching b.München,Germany

出　　处：《npj Computational Materials》2024年第1期1081-1090,共10页计算材料学(英文)

基　　金：We would like to thank the Deutsche Forschungsgemeinschaft(DFG)for financial support[Projects OR 349/3 and the Cluster of Excellence e-conversion(Grant No.EXC2089)];Grants for computer time from the Zentrum für Informationsdienste und Hochleistungsrechnen of TU Dresden and the Leibniz Computing Center Garching are gratefully acknowledged.

摘　　要：The substitution of heteroatoms and the functionalisation of molecules are established strategies in chemical synthesis.They target the precise tuning of the electronic properties of hydrocarbon molecules to improve their performance in various applications and increase their versatility.Modifications to the molecular structure often lead to simultaneous changes in the morphology such as different crystal structures.These changes can have a stronger and unpredictable impact on the targeted property.The complex relationships between substitution/functionalization in chemical synthesis and the resultingmodifications of properties in thin films or crystals are difficult to predict and remain elusive.Here we address these effects for charge carrier transport in organic crystals by combining simulations of carrier mobilities with crystal structure prediction based on density functional theory and density functional tight binding theory.This enables the prediction of carrier mobilities based solely on the molecular structure and allows for the investigation of chemical modifications prior to synthesis and characterisation.Studying nine specific molecules with tetracene and rubrene as reference compounds along with their combinedmodifications of themolecular cores and additional functionalisations,we unveil systematic trends for the carrier mobilities of their polymorphs.The positive effect of phenyl groups that is responsible for the marked differences between tetracene and rubrene can be transferred to other small molecules such as NDT and NBT leading to a mobility increase by large factors of about five.

关 键 词：theory CRYSTAL FUNCTIONAL 

分 类 号：O62[理学—有机化学]