title: Understanding the effects of the number of pyrazines and their positions on charge-transport properties in silylethynylated N-heteropentacenes.
abstract: The charge-transport properties of a series of silylethynylated N-heteropentacenes (TIPS-PEN-xN; x = 2, 4) were systematically investigated using Marcus electron-transfer theory coupled with kinetic Monte Carlo simulations. Electronic structure calculations showed that introducing more pyrazine rings decreases the energy levels of the lowest unoccupied molecular orbitals (LUMOs) and should aid electron transfer. The number and the positions of the pyrazine rings greatly influence the molecular packing in crystals and hence the intermolecular electronic coupling. Furthermore, the introduction of internal (rather than external) pyrazine rings leads to a better charge-transport network. Transport parameters evaluated from the hopping and band-like models both demonstrate that, among the TIPS-PEN-xN molecules, B-TIPS-PEN-4N-which has two internal pyrazine rings-is the most promising n-type material.
authors.affiliation: State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun, 130023, China.
authors.forename: Shou-Feng
authors.initials: SF
authors.lastname: Zhang
authors.forename: Xian-Kai
authors.initials: XK
authors.lastname: Chen
authors.forename: Jian-Xun
authors.initials: JX
authors.lastname: Fan
authors.forename: Jing-Fu
authors.initials: JF
authors.lastname: Guo
authors.forename: Ai-Min
authors.initials: AM
authors.lastname: Ren
authors.forename: Yu-Wei
authors.initials: YW
authors.lastname: Li
mesh_terms: D004583:Electrons; D004735:Energy Transfer; D008956:Models, Chemical; D056004:Molecular Dynamics Simulation; D015394:Molecular Structure; D009010:Monte Carlo Method; D009279:Naphthacenes / Q000737:chemistry*; D011719:Pyrazines / Q000737:chemistry*; D011789:Quantum Theory; D012666:Semiconductors; D012821:Silanes / Q000737:chemistry*; D013329:Structure-Activity Relationship
chemical_list: D009279:Naphthacenes; D011719:Pyrazines; D012821:Silanes; C523499:pentacene